Joining a match

What passes between a client and a server from connection until play begins, in order.

Starting a client

A client learns where to connect from its command line. It takes three arguments it needs nothing in, which can be empty, and then a fourth holding four words separated by single spaces: the server’s IPv4 address, its UDP port, the key (see Transport), and the player id the client registers as. The client connects to that address and port, registers as that player, and enciphers its proof under that key.

Any whitespace separates the words of the fourth argument. A client whose command line holds no double quote takes the command line it saved on an earlier run instead, and one holding .rep anywhere plays a replay rather than connecting.

Registering

A client’s first payload is Register, on the registration channel. The note on Registered says what a server answers with: one answer for every seat.

A client knows the answer meant for it by the player id it registered as, not by the client id, and takes the client id that answer carries as its own. Every other answer tells it which client id stands for which player.

A client waits 30 seconds for the answer naming its own player id. Then it offers its player to wait another 30 seconds or to give up, and leaves on giving up.

In 1.0.0.130–1.0.0.140

Every answer for its own player id, the first included, has a client send ReconnectedInMatch, saying whether play has yet begun.

Asking whether a server is ready

A client then sends QueryStatus over and over. A server MUST answer each one with QueryStatusAnswer, at least until it has answered that it is ready. While the answers say the server is not ready, a client stays on a black screen and keeps asking. A server that needs time before a match can begin answers that it is not ready until it is.

A client stops asking once an answer says the server is ready, and a query it sends after that answer needs none.

Stating a build

Once an answer says the server is ready, a client sends ClientVersion once. A server answers with VersionSync, and a client loads only where its agreement says the builds agree.

VersionSync names the map to load and everyone at the match.

Taking a seat

Straight after VersionSync, a client sends JoinSide on the roster channel. A server answers with one Roster, then a SeatName and a SeatChampion for each seat a player holds.

Loading

A client reports how far loading has got with LoadingProgress, repeatedly through loading. A server answers each report with SeatLoadProgress on the transient channel, carrying the report’s figures under the seat that reported. A client goes on reporting after its progress reaches 100, until play begins.

A client waits on no other seat. SpawnStart, SpawnEnd and StartGame are what move a client on, and StartGame alone ends its loading. A server that means its players to begin together sends StartGame to none of them until every client has sent ClientReady.

In 1.0.0.130–1.0.0.140

A server MUST put the seat’s player id in SeatLoadProgress: the loading screen shows a seat’s card from the VersionSync seat with that id.

In 1.0.0.140

A client writes its own client id where its player id goes in LoadingProgress, in the low four bytes with zeros above.

The loading screen

What a client draws while it loads comes from what it has been sent by then (see the spawn run below for what it takes before CharacterSelected).

A player’s card is built from several messages. Its place on the screen is that seat’s place in the Roster, and its name is that player’s SeatName. The registration answers (Registered) pair each player with a client id, and the latest SeatLoadProgress for that client gives the card its progress and, on the client’s own card only, its ping. The first SeatLoadProgress after the player’s SeatChampion sets the card up: its portrait and the champion’s name, from that SeatChampion’s champion and skin, then everything else from the VersionSync seat whose player id the SeatLoadProgress names. A card with no SeatChampion yet shows a black portrait, and one with no registration or no SeatLoadProgress yet says it is not connected. A later SeatChampion does not change a card already set up.

In 1.0.0.140

A card draws a seat’s icon only where it is 0 or more. A seat is a bot’s where its flags is not zero, whatever its bits, and the card of a bot takes its name from the client’s own name for that bot, not from the seat’s botName. No bit of flags chooses older portrait art.

The spawn run

Once a character is settled, a client sends CharacterSelected, once.

A server answers with SpawnStart, states everything on the field as play opens, and closes the run with SpawnEnd. A run carries:

for each seat, CreateChampion followed by Loadout;
for each turret, a CreateTurret and a Replication batch of its values;
for each inhibitor and nexus, an EnterSight, and a Replication batch on a map whose buildings replicate (see Replication);
a RegionAdded for each region, and a MapProp for each prop;
at a server’s choice, an EnterLocalSight for any of those units.

In 1.0.0.138–3.1.0.0

A turret’s CreateTurret can come on its own or inside the EnterSight that brings the turret into view.

A client takes these in any order within the run.

A run MUST carry at least SpawnStart, the CreateChampion carrying the client’s own client id, and SpawnEnd. Given only those, a client still enters play, showing its champion’s portrait, health, resource and spells. It draws the champion on the map only once an EnterSight places it there, with its name and health bar over it.

A client answers each Replication batch with a TransientAck naming that batch’s syncId. It sends one answer for each batch, in the order the batches came, including a batch that repeats the syncId of the batch before it.

A client answers a batch as soon as it arrives, within the run or not, and never answers one naming a unit it does not hold.

Starting play

A client sends ClientReady after SpawnEnd and after its answers to the run’s batches, while it is still reporting its loading. A server MUST answer with StartGame, and later sends MatchStarted, with other messages free to come between them; MatchStarted carries 0 (see Time).

A client sends ClientReady as soon as SpawnEnd arrives, and StartGame alone moves it into play.

In 1.0.0.130–1.0.0.140

A client whose connection drops before play begins ends rather than connecting again.

Messages

Each message of this system in this book, with each layout it has across the book’s patches and every note its definition carries. A layout is the message’s body, after the header its channel’s family puts in front (see Messages).

`Register`

What a client sends first. It arrives before the connection has a cipher state, so the payload travels in the clear apart from the proof.

Definition.

In 1.0.0.130–1.0.0.141

Command 0 on registration, sent by the client, reliable.

Field	Type	What it is
leading	bytes, 3	Arbitrary; it carries no meaning.
clientId	u32	A client writes zero here.
playerId	i64	Who the sender claims to be. The proof is what settles the claim.
proof	i64	The player id enciphered with the 16-byte key; a plain copy where the client has no key.

Vectors (1)

one-on-1-0-0-141

In 1.0.0.142–3.1.0.0

Command 0 on registration, sent by the client, reliable.

Field	Type	What it is
leading	bytes, 3	Arbitrary; it carries no meaning.
clientId	u32	A client writes zero here.
playerId	i64	Who the sender claims to be. The proof is what settles the claim.
version	u32	The build the client runs, with each part written out and run together, so 4.17.0.233 arrives as 41700233 and 4.17.0.267 as 41700267. A client always carries it, and the answer a server carries back repeats the same number.
proof	i64	The player id enciphered with the 16-byte key; a plain copy where the client has no key.
trailing	bytes, 4	Arbitrary; it carries no meaning.

`Registered`

What a server answers a registration with, naming a player in the match and the seat they occupy. It shares its command value with the request it answers, which travels the other way, and it is one fixed size.

Definition.

In 1.0.0.130–1.0.0.141

Command 0 on registration, sent by the server, reliable.

Field	Type	What it is
leading	bytes, 3	Unused; a server writes zero.
clientId	u32	The client id playerId holds. Where playerId is the client’s own, the client takes this client id as its own and goes on. A watching client takes the champion of the player holding this client id as its own, so a server answers one with a client id no player in the streamed match holds (see Watching a match).
playerId	i64	The player the answer is for; a client takes it only where this is its own player id, and reads nothing after it.

Vectors (1)

one-on-1-0-0-141

In 1.0.0.142–3.1.0.0

Command 0 on registration, sent by the server, reliable.

Straight after a request a server sends one answer for every seat, and every one of them carries that request’s build and proof back.

Field	Type	What it is
leading	bytes, 3	Unused; a server writes zero.
clientId	u32	The client id playerId holds. Where playerId is the client’s own, the client takes this client id as its own and goes on. A watching client takes the champion of the player holding this client id as its own, so a server answers one with a client id no player in the streamed match holds (see Watching a match).
playerId	i64	Who occupies that seat.
version	u32	The build the client said it runs. Where the answer follows a request, a server writes the number that request carried, and otherwise the build itself. A client ignores it.
proof	bytes, 8	The eight bytes a request fills with its proof. Where the answer follows a request, a server writes what that request carried, and otherwise zero. A client ignores them.
trailing	bytes, 4	Unused; a server writes zero.

`QueryStatus`

What a client sends to ask a server for its state. It carries nothing of its own. The header names no object: it carries zero.

Definition.

In every range of this book

Carried on requests, sent by the client, reliable, under these commands:

Builds	Command
1.0.0.130–1.0.0.143	23
1.0.0.144–3.1.0.0	20

No body.

Vectors (1)

one-on-1-0-0-143

`QueryStatusAnswer`

What a server returns when asked whether it is ready. The header names no object: a server writes zero.

Definition.

In every range of this book

Carried on events, sent by the server, reliable, under these commands:

Builds	Command
1.0.0.130–1.0.0.131	141
1.0.0.132–1.0.0.137	142
1.0.0.138	144
1.0.0.139–1.0.0.143	143
1.0.0.144–1.0.0.149	137
1.0.0.150–3.1.0.0	134

Field	Type	What it is
ready	u8	Whether the server is ready. While answers say it is not, a client keeps asking and goes no further, which Joining a match sets out. Values: 0 no, 1 yes.

Vectors (6)

yes-on-1-0-0-131, yes-on-1-0-0-136, yes-on-1-0-0-138, yes-on-1-0-0-143, yes-on-1-0-0-149, yes-on-1-0-0-154

`ClientVersion`

What a client sends to state which build it is. The header names no object: it carries zero.

Definition.

In 1.0.0.130–1.0.0.138

Carried on requests, sent by the client, reliable, under these commands:

Builds	Command
1.0.0.130–1.0.0.131	197
1.0.0.132–1.0.0.134	198
1.0.0.135	200
1.0.0.136–1.0.0.137	198
1.0.0.138	200

Field	Type	What it is
clock	f32	The client’s own clock as it sends this, in seconds.
clientId	u32	The client id of the client reporting.
text	text, 256 bytes	The build, as text. The text ends at a zero byte.

Vectors (5)

one-on-1-0-0-131, one-on-1-0-0-134, one-on-1-0-0-135, one-on-1-0-0-136, one-on-1-0-0-138

In 1.0.0.139–1.0.0.140

Command 199 on requests, sent by the client, reliable.

A client does not send it while watching a match.

Field	Type	What it is
clock	f32	The client’s own clock as it sends this, in seconds.
clientId	u32	The client id of the client reporting.
text	text, 256 bytes	The build as text: a fixed word, the build number, then the build type in square brackets. The text ends at a zero byte.

Vectors (1)

one-on-1-0-0-140

In 1.0.0.141–1.0.0.144

Carried on requests, sent by the client, reliable, under these commands:

Builds	Command
1.0.0.141–1.0.0.143	201
1.0.0.144	189

Field	Type	What it is
clock	f32	The client’s own clock as it sends this, in seconds.
clientId	u32	The client id of the client reporting.
text	text, 256 bytes	The build, as text. The text ends at a zero byte.

Vectors (2)

one-on-1-0-0-143, one-on-1-0-0-144

In 1.0.0.145–3.1.0.0

Carried on requests, sent by the client, reliable, under these commands:

Builds	Command
1.0.0.145–1.0.0.149	189
1.0.0.150–3.1.0.0	186

Field	Type	What it is
clientId	u32	The client id of the client reporting.
text	text, 256 bytes	The build, as text. The text ends at a zero byte.

Vectors (2)

one-on-1-0-0-149, one-on-1-0-0-154

`VersionSync`

What a server sends once a client has said which build it runs, saying whether the two agree. The header names no object: it carries zero.

Definition.

In 1.0.0.130–1.0.0.139

Carried on events, sent by the server, reliable, under these commands:

Builds	Command
1.0.0.130	87
1.0.0.131	87
1.0.0.132–1.0.0.137	88
1.0.0.138–1.0.0.139	90

It also says which map to load, who is at the match, and everything else settled before play.

Field	Type	What it is
agreement	u8	Nonzero where the build the client runs matches, which a client needs to load; zero has it show both versions and end.
map	i32	Which map to load. Space keys the path origins by the same maps.
seats	12 × Seat	Every place at the match, held or empty.
build	text, 256 bytes	Which build the server serves. Written out in full and padded with zero bytes to the width above.
mode	text, 128 bytes	Which way the match is played, written and padded as above.
teamName	text, 25 bytes	What one side is called where it plays as a standing team, written and padded as above.
teamTag	text, 7 bytes	The short form of that name, written and padded as above.
otherTeamName	text, 25 bytes	What the other side is called, under the same terms.
otherTeamTag	text, 7 bytes	The short form of that one.
metricsHost	text, 1024 bytes	Where a client reports figures about the match, written and padded as above.
metricsPath	text, 1024 bytes	What it asks for there, written and padded as above.
metricsPort	u16	Which port it reaches that at.
reporting	1-byte bits
reporting.reportsToFile	bit 0	Set to have a client also write its reports to a file of its own.
reporting.unused	bit 1 to 7	Unused; a server writes zero.

Vectors (4)

one-on-1-0-0-130, one-on-1-0-0-131, one-on-1-0-0-136, one-on-1-0-0-139

In 1.0.0.140–1.0.0.143

Command 90 on events, sent by the server, reliable.

It also says which map to load, who is at the match, and everything else settled before play.

Field	Type	What it is
agreement	u8	1 has a client load. 0 has it show both versions and end; any value from 2 to 255 also has it end, without showing them.
map	i32	Which map to load. Space keys the path origins by the same maps.
seats	12 × Seat	Every place at the match, held or empty.
build	text, 256 bytes	Which build the server serves. Written out in full and padded with zero bytes to the width above.
mode	text, 128 bytes	Which way the match is played, written and padded as above.
teamName	text, 25 bytes	What one side is called where it plays as a standing team, written and padded as above.
teamTag	text, 7 bytes	The short form of that name, written and padded as above.
otherTeamName	text, 25 bytes	What the other side is called, under the same terms.
otherTeamTag	text, 7 bytes	The short form of that one.
metricsHost	text, 1024 bytes	Where a client reports figures about the match, written and padded as above.
metricsPath	text, 1024 bytes	What it asks for there, written and padded as above.
metricsPort	u16	Which port it reaches that at.
reporting	1-byte bits
reporting.reportsToFile	bit 0	Set to have a client also write its reports to a file of its own.
reporting.matched	bit 1	Set to hide all chat: a client refuses to send a line to all players and shows a notice instead, a different one where it is watching the match.
reporting.unused	bit 2 to 7	Unused; a server writes zero.

Vectors (1)

one-on-1-0-0-143

In 1.0.0.144

Command 84 on events, sent by the server, reliable.

It also says which map to load, who is at the match, and everything else settled before play.

Field	Type	What it is
agreement	u8	Nonzero where the build the client runs matches, which a client needs to load; zero has it show both versions and end.
map	i32	Which map to load. Space keys the path origins by the same maps.
seats	12 × Seat	Every place at the match, held or empty.
build	text, 256 bytes	Which build the server serves. Written out in full and padded with zero bytes to the width above.
mode	text, 128 bytes	Which way the match is played, written and padded as above.
teamName	text, 25 bytes	What one side is called where it plays as a standing team, written and padded as above.
teamTag	text, 7 bytes	The short form of that name, written and padded as above.
otherTeamName	text, 25 bytes	What the other side is called, under the same terms.
otherTeamTag	text, 7 bytes	The short form of that one.
metricsHost	text, 1024 bytes	Where a client reports figures about the match, written and padded as above.
metricsPath	text, 1024 bytes	What it asks for there, written and padded as above.
metricsPort	u16	Which port it reaches that at.
reporting	1-byte bits
reporting.reportsToFile	bit 0	Set to have a client also write its reports to a file of its own.
reporting.matched	bit 1	Set where the match was put together rather than made by hand.
reporting.unused	bit 2 to 7	Unused; a server writes zero.

Vectors (1)

one-on-1-0-0-144

In 1.0.0.145–1.0.0.146

Command 84 on events, sent by the server, reliable.

It also says which map to load, who is at the match, and everything else settled before play.

Field	Type	What it is
agreement	u8	Nonzero where the build the client runs matches, which a client needs to load; zero has it show both versions and end.
map	i32	Which map to load. Space keys the path origins by the same maps.
seats	12 × Seat	Every place at the match, held or empty.
build	text, 256 bytes	Which build the server serves. Written out in full and padded with zero bytes to the width above.
mode	text, 128 bytes	Which way the match is played, written and padded as above.
teamName	text, 25 bytes	What one side is called where it plays as a standing team, written and padded as above.
teamTag	text, 7 bytes	The short form of that name, written and padded as above.
otherTeamName	text, 25 bytes	What the other side is called, under the same terms.
otherTeamTag	text, 7 bytes	The short form of that one.
metricsHost	text, 1024 bytes	Where a client reports figures about the match, written and padded as above.
metricsPath	text, 1024 bytes	What it asks for there, written and padded as above.
metricsPort	u16	Which port it reaches that at.
reporting	1-byte bits
reporting.reportsToFile	bit 0	Set to have a client also write its reports to a file of its own.
reporting.matched	bit 1	Set where the match was put together rather than made by hand.
reporting.unused	bit 2 to 7	Unused; a server writes zero.
tip	i8	Which note the client shows before play, as it stands. A client watching a recorded match takes both bytes below as zero.
tipColour	i8	Kept by the client, which reads nothing more from it.
tipDuration	i8	Kept by the client, which reads nothing more from it.
loadingTips	u8	Nonzero shows the note on the loading screen.
playingTips	u8	Nonzero shows it during play, from time to time.

Vectors (1)

one-on-1-0-0-146

In 1.0.0.147–1.0.0.149

Command 84 on events, sent by the server, reliable.

It also says which map to load, who is at the match, and everything else settled before play.

Field	Type	What it is
agreement	1-byte bits
agreement.buildMatches	bit 0	Set where the client’s build is one the server serves.
agreement.reportsToFile	bit 1	Set to have a client also write its reports to a file of its own.
agreement.matched	bit 2	Set where the match was put together rather than made by hand.
agreement.unused	bit 3 to 7	Unused; a server writes zero.
map	i32	Which map to load. Space keys the path origins by the same maps.
seats	12 × Seat	Every place at the match, held or empty.
build	text, 256 bytes	Which build the server serves. Written out in full and padded with zero bytes to the width above.
mode	text, 128 bytes	Which way the match is played, written and padded as above.
teamName	text, 25 bytes	What one side is called where it plays as a standing team, written and padded as above.
teamTag	text, 7 bytes	The short form of that name, written and padded as above.
otherTeamName	text, 25 bytes	What the other side is called, under the same terms.
otherTeamTag	text, 7 bytes	The short form of that one.
metricsHost	text, 1024 bytes	Where a client reports figures about the match, written and padded as above.
metricsPath	text, 1024 bytes	What it asks for there, written and padded as above.
metricsPort	u16	Which port it reaches that at.
tip	i8	Which note the client shows before play, as it stands. A client watching a recorded match takes both bytes below as zero.
tipColour	i8	Kept by the client, which reads nothing more from it.
tipDuration	i8	Kept by the client, which reads nothing more from it.
loadingTips	u8	Nonzero shows the note on the loading screen.
playingTips	u8	Nonzero shows it during play, from time to time.

Vectors (2)

one-on-1-0-0-147, one-on-1-0-0-149

In 1.0.0.150–3.1.0.0

Command 81 on events, sent by the server, reliable.

It also says which map to load, who is at the match, and everything else settled before play.

Field	Type	What it is
agreement	1-byte bits
agreement.buildMatches	bit 0	Set where the client’s build is one the server serves.
agreement.reportsToFile	bit 1	Set to have a client also write its reports to a file of its own.
agreement.matched	bit 2	Set where the match was put together rather than made by hand.
agreement.unused	bit 3 to 7	Unused; a server writes zero.
map	i32	Which map to load. Space keys the path origins by the same maps.
seats	12 × Seat	Every place at the match, held or empty.
build	text, 256 bytes	Which build the server serves. Written out in full and padded with zero bytes to the width above.
mode	text, 128 bytes	Which way the match is played, written and padded as above.
teamName	text, 25 bytes	What one side is called where it plays as a standing team, written and padded as above.
teamTag	text, 7 bytes	The short form of that name, written and padded as above.
otherTeamName	text, 25 bytes	What the other side is called, under the same terms.
otherTeamTag	text, 7 bytes	The short form of that one.
metricsHost	text, 1024 bytes	Where a client reports figures about the match, written and padded as above.
metricsPath	text, 1024 bytes	What it asks for there, written and padded as above.
metricsPort	u16	Which port it reaches that at.
tip	i8	Which note the client shows before play.
tipColour	i8	Which colouring it shows it in.
tipDuration	i8	Which display time to hold the note up for, applying only where tips are enabled and shown somewhere. tip, tipColour and tipDuration each select one of the notes, colourings and display times a client defines, tip counted modulo the number of notes. Where a value selects none, or the time is not above zero, a client shows no note.
tipFlags	1-byte bits	How the note is shown. A client sends these four bytes back in ClientReady, as it has corrected them.
tipFlags.enabled	bit 0	Set where there is a note. A client shows the note only where this and loadingScreen or inGame are set, and shows none where tip, tipColour or tipDuration names nothing.
tipFlags.replay	bit 1	Of no effect; a client clears it, with enabled, while playing a replay.
tipFlags.loadingScreen	bit 2	Set to show the note on the loading screen.
tipFlags.inGame	bit 3	Set to show the note during play, in a box on the screen.
tipFlags.cycle	bit 4	Set to have the box during play show every note in turn.
tipFlags.unused	bit 5 to 7	Unused; a server writes zero.

Vectors (2)

one-on-1-0-0-150, one-on-1-0-0-154

`JoinSide`

What a client sends to ask for a seat on one of the two sides while the match is being put together.

Definition.

In 1.0.0.130–1.0.0.146

Command 100 on roster, sent by the client, reliable.

Field	Type	What it is
padding	bytes, 3	Never written by a client.
clientId	u32	The client id of the client asking.
side	u32	The side it asks for.

Vectors (1)

one-on-1-0-0-146

In 1.0.0.147–3.1.0.0

Command 100 on roster, sent by the client, reliable.

Field	Type	What it is
clientId	u32	The client id of the client asking.
side	u32	The side it asks for.

`Roster`

What a server sends to lay out both sides and who is on them, while the match is being put together.

Definition.

In 1.0.0.130–1.0.0.146

Command 103 on roster, sent by the server, reliable.

Field	Type	What it is
padding	bytes, 3	Unused; a client reads nothing here.
sideRoom	u32	How many seats the first side has room for, and so how many leading places of side a client copies. A server sends at most 24: a client refuses a count above 48 and keeps the one before, and for 25 to 48 copies on past the side’s places into the fields after them.
otherSideRoom	u32	How many the other has room for, under the same terms.
gap	bytes, 4	Unused; a client reads nothing here.
side	24 × i64	The players on one side, twenty four places. A client copies as many leading places as sideRoom gives; the rest hold zero. A place cannot be read on its own, because zero is an identifier a match gives out as well as what an unused place holds. It has a player identifier’s width.
otherSide	24 × i64	The players on the other, under the same reading, as many as otherSideRoom gives.
sideTaken	u32	How many of the leading places on the first side carry a player. A client keeps it, and it limits nothing.
otherSideTaken	u32	How many on the other, under the same terms.

Vectors (1)

one-on-1-0-0-146

In 1.0.0.147–3.1.0.0

Command 103 on roster, sent by the server, reliable.

Field	Type	What it is
sideRoom	u32	How many seats the first side has room for.
otherSideRoom	u32	How many the other has room for.
side	24 × i64	The players on one side, twenty four places. The count below says how many of the leading places carry a player; the rest hold zero. A place cannot be read on its own, because zero is an identifier a match gives out as well as what an unused place holds. It has a player identifier’s width.
otherSide	24 × i64	The players on the other, under the same reading and its own count.
sideTaken	u32	How many of the leading places on the first side carry a player.
otherSideTaken	u32	How many on the other.

`SeatName`

What a server sends to say what a seat is called, while the match is being put together.

Definition.

In 1.0.0.130–1.0.0.146

Command 102 on roster, sent by the server, reliable.

Field	Type	What it is
padding	bytes, 7	Unused; a client reads nothing here.
player	i64	The player this is about. It has a player identifier’s width.
skin	i32	Which look the seat’s champion wears. A client reads nothing here.
nameLength	u32	How many bytes the name below occupies, counting the byte that ends it. A client reads nothing here: it reads the name up to its zero byte.
name	text, sized by nameLength minus 1	What the seat is called. It is not padded.
terminator	bytes, 1	A zero byte closing the text, which the length above counts.

Vectors (1)

one-on-1-0-0-146

In 1.0.0.147–3.1.0.0

Command 102 on roster, sent by the server, reliable.

Field	Type	What it is
player	i64	The player this is about. It has a player identifier’s width.
skin	i32	Which look the seat’s champion wears.
nameLength	u32	How many bytes the name below occupies, counting the byte that ends it.
name	text, sized by nameLength minus 1	What the seat is called. It is not padded.
terminator	bytes, 1	A zero byte closing the text, which the length above counts.

`SeatChampion`

What a server sends to say which champion a seat is playing, while the match is being put together.

Definition.

In 1.0.0.130–1.0.0.146

Command 101 on roster, sent by the server, reliable.

Field	Type	What it is
padding	bytes, 7	Unused; a client reads nothing here.
player	i64	The player this is about. It has a player identifier’s width.
skin	i32	Which look the champion wears.
assetLength	u32	How many bytes the name below occupies, counting the byte that ends it.
asset	text, sized by assetLength minus 1	The name the client loads the champion’s art and sound under. It is not padded.
terminator	bytes, 1	A zero byte closing the text, which the length above counts.

Vectors (1)

one-on-1-0-0-146

In 1.0.0.147–3.1.0.0

Command 101 on roster, sent by the server, reliable.

Field	Type	What it is
player	i64	The player this is about. It has a player identifier’s width.
skin	i32	Which look the champion wears.
assetLength	u32	How many bytes the name below occupies, counting the byte that ends it.
asset	text, sized by assetLength minus 1	The name the client loads the champion’s art and sound under. It is not padded.
terminator	bytes, 1	A zero byte closing the text, which the length above counts.

`LoadingProgress`

What a client sends while a match loads, saying how far it has got. The header names no object: it carries zero.

Definition.

In 1.0.0.130–1.0.0.143

Command 25 on requests, sent by the client, unreliable.

Field	Type	What it is
clientId	u32	The client id of the client reporting.
playerId	i64	Who is reporting. A client sends zero.
percent	f32	How far loading has got, from zero to one hundred.
eta	f32	How long the client expects still to take, in seconds.
status	4-byte bits
status.count	bit 0 to 15	It rises with each report, not always by one.
status.ping	bit 16 to 30	Round trip time the client measures, in milliseconds.
status.unused	bit 31	Never written by a client.
done	1-byte bits
done.loaded	bit 0	Set in every report whose progress stands at one hundred, and in no other.
done.unused	bit 1 to 7	Never written by a client.

Vectors (1)

one-on-1-0-0-143

In 1.0.0.144–1.0.0.146

Command 22 on requests, sent by the client, unreliable.

Field	Type	What it is
clientId	u32	The client id of the client reporting.
playerId	i64	Who is reporting. A client sends every bit set, which names nobody.
percent	f32	How far loading has got, from zero to one hundred.
eta	f32	How long the client expects still to take, in seconds.
status	4-byte bits
status.count	bit 0 to 15	It rises with each report, not always by one.
status.ping	bit 16 to 30	Round trip time the client measures, in milliseconds.
status.unused	bit 31	Never written by a client.
done	1-byte bits
done.loaded	bit 0	Set in every report whose progress stands at one hundred, and in no other.
done.unused	bit 1 to 7	Never written by a client.

Vectors (1)

one-on-1-0-0-146

In 1.0.0.147–3.1.0.0

Command 22 on requests, sent by the client, unreliable.

Field	Type	What it is
clientId	u32	The client id of the client reporting.
playerId	i64	Who is reporting. A client sends every bit set, which names nobody.
percent	f32	How far loading has got, from zero to one hundred.
eta	f32	How long the client expects still to take, in seconds.
status	4-byte bits
status.count	bit 0 to 15	It rises with each report, not always by one.
status.ping	bit 16 to 30	Round trip time the client measures, in milliseconds.
status.loaded	bit 31	Set in every report whose progress stands at one hundred, and in no other.

`SeatLoadProgress`

What a server sends to tell everyone how far one seat has got through loading, and how it is holding up. A later report supersedes an earlier one, so losing one costs nothing. The header names no object: a server writes zero.

Definition.

In 1.0.0.130–1.0.0.133

Carried on transient, sent by the server, unreliable, under these commands:

Builds	Command
1.0.0.130–1.0.0.131	157
1.0.0.132–1.0.0.133	158

Field	Type	What it is
clientId	u32	The client id this is about.
player	i64	Who occupies it.
progress	f32	How far through loading it is, from zero to one hundred.
secondsLeft	f32	How much longer it is expected to take, in seconds.
status	4-byte bits	Copied with the rest; no reader of it is known.
status.count	bit 0 to 15	It rises with each report, not always by one.
status.ping	bit 16 to 30	Round trip time the client measures, in milliseconds.
status.loaded	bit 31	Set in every report whose progress stands at one hundred, and in no other.
done	1-byte bits
done.loaded	bit 0	Set where the seat has loaded; a client then shows no time left.
done.unused	bit 1 to 7	Unused; a server writes zero.

Vectors (2)

one-on-1-0-0-131, one-on-1-0-0-133

In 1.0.0.134–3.1.0.0

Carried on transient, sent by the server, unreliable, under these commands:

Builds	Command
1.0.0.134	158
1.0.0.135	160
1.0.0.136–1.0.0.137	158
1.0.0.138	160
1.0.0.139–1.0.0.143	159
1.0.0.144–1.0.0.149	149
1.0.0.150–3.1.0.0	146

Field	Type	What it is
clientId	u32	The client id this is about.
player	i64	Who occupies it.
progress	f32	How far through loading it is, from zero to one hundred.
secondsLeft	f32	How much longer it is expected to take, in seconds.
status	4-byte bits
status.count	bit 0 to 15	It rises with each report, not always by one.
status.ping	bit 16 to 30	Round trip time the client measures, in milliseconds.
status.loaded	bit 31	Set in every report whose progress stands at one hundred, and in no other.

Vectors (7)

one-on-1-0-0-134, one-on-1-0-0-135, one-on-1-0-0-136, one-on-1-0-0-138, one-on-1-0-0-143, one-on-1-0-0-149, one-on-1-0-0-154

`SpawnStart`

What a server sends to open the run of units a client is about to be told about. The header names no object: a server writes zero.

Definition.

In every range of this book

Carried on events, sent by the server, reliable, under these commands:

Builds	Command
1.0.0.130–1.0.0.131	101
1.0.0.132–1.0.0.137	102
1.0.0.138–1.0.0.143	104
1.0.0.144–1.0.0.149	98
1.0.0.150–3.1.0.0	95

Field	Type	What it is
botsOnOneSide	u8	How many bots play on side 100. A client adds it to that side’s head count, which picks the set of spawn positions and facings it places champions by (CreateChampion’s spawnIndex).
botsOnTheOther	u8	The other. It shares the reading above.

Vectors (5)

one-on-1-0-0-131, one-on-1-0-0-136, one-on-1-0-0-143, one-on-1-0-0-149, one-on-1-0-0-154

`SpawnEnd`

What a server sends to close the run of units it opened with. The header names no object: a server writes zero.

Definition.

In every range of this book

Carried on events, sent by the server, reliable, under these commands:

Builds	Command
1.0.0.130–1.0.0.143	18
1.0.0.144–3.1.0.0	17

No body.

Vectors (1)

one-on-1-0-0-143

`StartGame`

What a server sends to begin play. The header names no object: it carries zero.

Definition.

In 1.0.0.130–1.0.0.131

Command 95 on events, sent by the server, reliable.

A client ignores it once the match has ended or while it is leaving, and acts on it again where it is repeated.

Field	Type	What it is
rules	1-byte bits
rules.pausing	bit 0	Where set, a client announces that pausing is allowed, except while playing a replay. It keeps nothing of it.
rules.unused	bit 1 to 7	Unused; a server writes zero.

Vectors (1)

one-on-1-0-0-131

In 1.0.0.132–1.0.0.137

Command 96 on events, sent by the server, reliable.

A client past spawning ignores it.

Field	Type	What it is
rules	1-byte bits
rules.pausing	bit 0	Set where holding the match is allowed.
rules.unused	bit 1 to 7	Unused; a server writes zero.

Vectors (1)

one-on-1-0-0-136

In 1.0.0.138–1.0.0.143

Command 98 on events, sent by the server, reliable.

A client skips the start only once the match has ended or it is leaving: after GameEnded, Shutdown or an exit. Before, during and after spawning, it starts again.

Field	Type	What it is
rules	1-byte bits
rules.pausing	bit 0	Set to have a client that is not watching the match show a notice in its chat that pausing is allowed. A client keeps nothing of it, and it limits no pausing.
rules.unused	bit 1 to 7	Unused; a server writes zero.

Vectors (1)

one-on-1-0-0-143

In 1.0.0.144–1.0.0.145

Command 92 on events, sent by the server, reliable.

A client past spawning ignores it.

Field	Type	What it is
rules	1-byte bits
rules.pausing	bit 0	Set where holding the match is allowed.
rules.unused	bit 1 to 7	Unused; a server writes zero.

Vectors (1)

one-on-1-0-0-145

In 1.0.0.146

Command 92 on events, sent by the server, reliable.

A client past spawning ignores it.

Field	Type	What it is
rules	1-byte bits
rules.pausing	bit 0	Set where holding the match is allowed.
rules.notice	bit 1	Set to post a notice in chat as play begins.
rules.unused	bit 2 to 7	Unused; a server writes zero.

Vectors (1)

one-on-1-0-0-146

In 1.0.0.147–3.1.0.0

Carried on events, sent by the server, reliable, under these commands:

Builds	Command
1.0.0.147–1.0.0.149	92
1.0.0.150–3.1.0.0	89

A client past spawning ignores it.

Field	Type	What it is
rules	1-byte bits
rules.pausing	bit 0	Set where holding the match is allowed.
rules.unused	bit 1 to 7	Unused; a server writes zero.

Vectors (2)

one-on-1-0-0-149, one-on-1-0-0-154

`ClientReady`

What a client sends once it has loaded and is ready to play. The header names no object: it carries zero.

Definition.

In 1.0.0.130–1.0.0.132

Carried on requests, sent by the client, reliable, under these commands:

Builds	Command
1.0.0.130–1.0.0.131	85
1.0.0.132	86

No body.

Vectors (2)

one-on-1-0-0-131, one-on-1-0-0-132

In 1.0.0.133–1.0.0.137

Command 86 on requests, sent by the client, reliable.

Field	Type	What it is
maskedStatus	u32	It varies from client to client; a server ignores it.
mask	u32	A random value the client picks to mask the one above.

Vectors (1)

one-on-1-0-0-136

In 1.0.0.138–1.0.0.143

Command 88 on requests, sent by the client, reliable.

It comes unprompted, before any start of play reaches the client.

Field	Type	What it is
maskedStatus	u32	A status, masked. Taken by exclusive or with mask and with the client’s own champion id, it gives 262917615 where the client’s check of itself found a fault, and any other value otherwise. While watching a match, a client leaves this and mask unset, so they carry no meaning.
mask	u32	A random value the client picks to mask the one above.

Vectors (1)

one-on-1-0-0-143

In 1.0.0.144

Command 82 on requests, sent by the client, reliable.

Field	Type	What it is
maskedStatus	u32	It varies from client to client; a server ignores it.
mask	u32	A random value the client picks to mask the one above.

Vectors (1)

one-on-1-0-0-144

In 1.0.0.145–1.0.0.149

Command 82 on requests, sent by the client, reliable.

The tip fields carry VersionSync’s tip bytes, each one outside its valid range negated (0 as -128), and tips cleared where any is. Playing a replay, a client sends all four as zero.

Field	Type	What it is
maskedStatus	u32	It varies from client to client; a server ignores it.
mask	u32	A random value the client picks to mask the one above.
tipChosen	u8	Which tip the client is set to show.
tipColour	u8	How it is coloured.
tipDuration	u8	How long it stays, as an entry among the display times in the client’s own settings rather than a length of time.
loadingTips	u8	As VersionSync gave it.
playingTips	u8	As VersionSync gave it.

Vectors (1)

one-on-1-0-0-149

In 1.0.0.150–3.1.0.0

Command 79 on requests, sent by the client, reliable.

The tip fields carry VersionSync’s tip bytes, each one outside its valid range negated (0 as -128), and tips cleared where any is. Playing a replay, a client sends all four as zero.

Field	Type	What it is
maskedStatus	u32	It varies from client to client; a server ignores it.
mask	u32	A random value the client picks to mask the one above.
tipChosen	u8	Which tip the client is set to show.
tipColour	u8	How it is coloured.
tipDuration	u8	How long it stays, as an entry among the display times in the client’s own settings rather than a length of time.
settings	1-byte bits
settings.tips	bit 0	Set while tips are wanted at all.
settings.reporting	bit 1	Set while the client reports on itself.
settings.loadingTips	bit 2	Set while tips are wanted while loading.
settings.playingTips	bit 3	Set while tips are wanted during play.
settings.debug	bit 4	Set while the client runs in a debugging state.
settings.unused	bit 5 to 7	A client returns them as the server sent them.

Vectors (1)

one-on-1-0-0-154

`CharacterSelected`

What a client sends once a character is settled on. It carries nothing of its own. The header names no object: it carries zero.

Definition.

In every range of this book

Carried on requests, sent by the client, reliable, under these commands:

Builds	Command
1.0.0.130–1.0.0.131	198
1.0.0.132–1.0.0.134	199
1.0.0.135	201
1.0.0.136–1.0.0.137	199
1.0.0.138	201
1.0.0.139–1.0.0.140	200
1.0.0.141–1.0.0.143	202
1.0.0.144–1.0.0.149	190
1.0.0.150–3.1.0.0	187

No body.

Vectors (9)

one-on-1-0-0-131, one-on-1-0-0-134, one-on-1-0-0-135, one-on-1-0-0-136, one-on-1-0-0-138, one-on-1-0-0-140, one-on-1-0-0-143, one-on-1-0-0-149, one-on-1-0-0-154

`MatchIdentity`

What a server sends to tell a client which match this is and what its player is called. The header carries zero.

Definition.

In 1.0.0.130–1.0.0.149

Carried on events, sent by the server, reliable, under these commands:

Builds	Command
1.0.0.130–1.0.0.131	152
1.0.0.132–1.0.0.134	153
1.0.0.135	155
1.0.0.136–1.0.0.137	153
1.0.0.138	155
1.0.0.139–1.0.0.143	154
1.0.0.144–1.0.0.149	146

Field	Type	What it is
game	i64	The match’s identifier.
name	text, 128 bytes	The player’s name, padded with zero bytes.

Vectors (7)

one-on-1-0-0-131, one-on-1-0-0-134, one-on-1-0-0-135, one-on-1-0-0-136, one-on-1-0-0-138, one-on-1-0-0-143, one-on-1-0-0-149

In 1.0.0.150–3.1.0.0

Command 143 on events, sent by the server, reliable.

Field	Type	What it is
game	i64	The match’s identifier.
platform	text, 32 bytes	Which platform the match belongs to, written and padded as above.
name	text, 128 bytes	The player’s name, padded with zero bytes.

Vectors (1)

one-on-1-0-0-154

`MatchStarted`

What a server sends to set when the match began. The header names no object: it carries zero.

Definition.

In every range of this book

Carried on events, sent by the server, reliable, under these commands:

Builds	Command
1.0.0.130–1.0.0.131	202
1.0.0.132–1.0.0.134	203
1.0.0.135	205
1.0.0.136–1.0.0.137	203
1.0.0.138	205
1.0.0.139–1.0.0.140	204
1.0.0.141–1.0.0.143	206
1.0.0.144–1.0.0.149	194
1.0.0.150–3.1.0.0	191

Field	Type	What it is
startedAt	f32	When the match began, as a moment on the match clock, in seconds.

Vectors (9)

one-on-1-0-0-131, one-on-1-0-0-134, one-on-1-0-0-135, one-on-1-0-0-136, one-on-1-0-0-138, one-on-1-0-0-140, one-on-1-0-0-143, one-on-1-0-0-149, one-on-1-0-0-154

`ModulePacket`

What a client sends to carry data from a module of its own, often a message of its own that the module has taken over. A server need do nothing with it. The header carries zero.

Definition.

In 1.0.0.130–1.0.0.131

Command 237 on requests, sent by the client, reliable.

Field	Type	What it is
kind	u16	999 where the client passed the data through its own transform, 2 where it did not. A client sends both under command 237; a second sender sends 999 under 236. Nothing is sent under 238.
length	u16	How many bytes of the data below carry anything, at most 1024.
data	bytes, 1024	The data, in its first length bytes; a client leaves the rest unwritten.

Vectors (1)

one-on-1-0-0-131

In 1.0.0.132–1.0.0.134

Command 238 on requests, sent by the client, reliable.

Field	Type	What it is
kind	u16	999 where the client passed the data through its own transform, 2 where it did not. A client sends kind 999 under command 237 and kind 2 under 238.
length	u16	How many bytes of the data below carry anything, at most 1024.
data	bytes, 1024	The data, in its first length bytes; a client leaves the rest unwritten.

Vectors (1)

one-on-1-0-0-134

In 1.0.0.135–1.0.0.139

Carried on requests, sent by the client, reliable, under these commands:

Builds	Command
1.0.0.135	235
1.0.0.136–1.0.0.137	233
1.0.0.138	235
1.0.0.139	234

Field	Type	What it is
kind	u16	999 where the client passed the data through its own transform, 2 where it did not.
length	u16	How many bytes of the data below carry anything, at most 1024.
data	bytes, 1024	The data, in its first length bytes; a client leaves the rest unwritten.

Vectors (4)

one-on-1-0-0-135, one-on-1-0-0-136, one-on-1-0-0-138, one-on-1-0-0-139

In 1.0.0.140

Command 234 on requests, sent by the client, reliable.

Field	Type	What it is
kind	u8	What the data is for.
extra	u8	The first byte of the module’s data from one sender, the command itself from the others; nothing a server needs.
length	u16	How many bytes of data follow; at most 1024.
data	bytes, sized by length	Data for a module of the client’s own, which the message only carries.

Vectors (1)

one-on-1-0-0-140

In 1.0.0.141–3.1.0.0

Carried on requests, sent by the client, reliable, under these commands:

Builds	Command
1.0.0.141–1.0.0.143	236
1.0.0.144–1.0.0.149	223
1.0.0.150–3.1.0.0	220

Field	Type	What it is
kind	u8	What the data is for.
length	u16	How many bytes of data follow; at most 1024.
data	bytes, sized by length	Data for a module of the client’s own, which the message only carries.