Update 25 Sep
- "Create friendly games" is now available to premium members that have opted into beta (https://www.chess.com/beta). Only the creator of a friendly needs premium, anyone can be invited.
- New friendly variants include N-check (each player has N "lives", the final check is checkmate), King of the Hill, and 960, or any combination of those! You can also set a custom starting position.
- Country flags, online status (green/orange square indicator in avatar), full name and best rating in user popup (hover over username)
- Integrated club chat.
- You can no longer set your rating range to exclude players within 100 points of your own rating
Bug fixes:
Observers (no more 'unknown')
Team rating range when inviting
Update 13 Sep
- reintroduced cancelling game if not all players connected at game start.
- fixed low time sound? (please report if you have sound problems. it's browser dependent)
Update 12 Sep
- removed cancelling games because some players got stuck in them.
- changed shortcuts for blindfold and ghost board to SHIFT-B/G
- introduced low time sound bug?
11 Sep 2018 Released all features of the new version.
Rule Changes
- To appear on the leaderboard, you need to have played 3 games in the last two weeks. You also need to have played at least 25 games total (since Aug 7 release). At the time of release we only have the date of your most recent game, and this game will count as 3 until it "expires" (is >14 days ago).
- FFA rating changes have been increased.
- You can no longer set your rating range to exclude players weaker than your own rating + 100.
- The rating loss for causing an abort depends on how frequently you have aborted games. Very frequent aborting will result in a temporary play-ban.
- Each player must make their first move within 30 seconds (before 0:45), or the game will be aborted.
New features
- Game archive: all games (since aug 7 release) can now be found in the archive. Click the + on the far right of the search form to get more search options (2nd player, result (of first player), custom time span. The results can be sorted by date, number of moves (plies), or duration.
- Analysis board (Keyboard shurtcut: A, or click New Game and choose Analysis board from the dropdown). The game replayer can also be used for analysis.
- PGN4: save and share your lines, variations and annontations.
- Edit position: Set up any position and “continue from here”. Save and share positions with FEN4.
- Rematch: If all players click the rematch button, a new game will start with random seating (for teams, the other team will get Red).
Note: the Rematch button is only available as long as all 4 players remain in the room (eliminated FFA players usually leave the room before the game ends). The number on the button indicates how many players want to rematch.
EDIT: do to problems with the observers this feature is currently not likely to work. - Report abuse: report form accessible via the ! icon in the player popup.
- Separate rating range setting for Teams and FFA.
- Fullscreen/Focus mode: collapse the board panel. shortcut: F, or click the collapse icon (next to settings icon).
- You can drag or select a piece before it's your turn and drop it once your turn is reached. Dropping before your turn will cancel the drag. (right-clicking will now also cancel the move.)
- Drag the panel divider (just below the |< << < > >> >| buttons) to change the space available for moves vs chat.
- Games you visited are slighlty dimmed in the list (top games and archive). Reloading the page will reset "memory"
- Go back (to the last game you opened) -icon (located in same place as the exit-button)
- Use the link icon (top right) for a link to the current game.
- link to game and move https://www.chess.com/4-player-chess?g=123-45 (game #123 at ply 45. -ply is optional)
- link to archive search https://www.chess.com/4-player-chess?p=e4bc4qh5qf7 - Rotate the board (compass-icon above moves list, shortcut R)
- Automatically rotate the board to the player who's turn it is. (icon next to compass. shortcut T)
- Settings are now saved in your account (used to be saved in browser)
- Transparent arrows (shortcut W)
- Piece animation speed setting
- Panel transparency setting
- Blindfold mode (Shortcut Shift+B)
- Colored moves (shortcut M): colorful indications in the moves list of which and whose piece was captured or who was checked/mated.
- Profanity filter
Fixed:
- MS Edge bug
- phantom piece bug
- layout for safari10
- top games sorting
- Help page (shortcut H)
ⓘ Shift-clicking any piece show's it's legal moves.
Keyboard shortcuts:
← → ↑ ↓
, (comma) Start
. (dot) End
Backspace/Delete Takeback
Escape Exit Room/Game
A Analysis mode
S Settings
H Help
R Rotate board
T Auto-rotate <font data-v-fe1f2c4c="" size="-2">(by turn)</font>
F Focus mode <font data-v-fe1f2c4c="" size="-2">(collapse board panel)</font>
L Coordinates
K Coordinate-Helper (show coordinate on mouse-over-square)
W Transparent arrows
M Colored move annotation
Shift-B Blindfold
Shift-G Ghost board (bug turned feature 
)
Right-click-drag to draw arrows.
Choose arrow color by holding key 1, 2,
3 or 4 pressed on your keyboard.
Click the board to clear all arrows.
Shift-click to clear only your own arrows.
In games you played in, your arrows are
shared (and are of your color) when you
are not alone in the room.
In analysis mode (shortcut A), you can
change the game type, and edit player names,
ratings or points by clicking on them.
Alternatively, edit the PGN4 and press ↑ Load.
Please consider going premium to get the max out of these new features by freeing up the ad space for them! Support Four Player Chess! Thanks!
07 Aug 2018 A new version of 4PC (beta) released.
Changes in the game rules:
- Checking three players simultaneously: +20 points.
- A king can now capture resigned kings.
- Resign or timeout in FFA: If a player resigns or times out before having made at least 4 moves, he will lose rating (-10 points currently) and the game will be aborted.
- Resign or timeout in Teams Mode: If a player resigns or times out on his first move, he will lose rating (-10 points currently) and the game will be aborted.
New features and improvements:
- Glicko rating system (instead of ELO).
- Colorblind mode. (Red pieces become white. Green become black.)
- Early resign or timeout leads to the game being aborted, and the resigner loses 10 rating points.
- There can be a draw in Teams Mode games now.
- A pop-up box with player rating and other information.
- Legal move indicators.
- Shift+click any piece to see its legal moves at any moment.
- A button to invite the same teammate again in the Teams Mode. (Rematch with the partner you just played with.)
- Captured pieces are now displayed.
- Shift+click on an empty square to clear only your own arrows.
- Clearing your arrows also clears them from your partner's (and observers') boards.
- Observers can draw (orange) arrows for themselves.
- It is possible to draw arrows after a game.
- Single square arrows are shown as circles.
- An option to hide teammate's arrows.
- An option to hide coordinates.
- A dot in the center of the FFA board to help find the squares where pawns become queens.
- (a dozen or more of minor improvements like new sounds, visual effects, etc.)
More info with screenshots:
https://www.chess.com/clubs/forum/view/please-help-us-test-the-new-version-of-4-player-chess
P.S. Old changelog:
https://www.chess.com/clubs/forum/view/changelog-9-04-2017
June 8th, 2020
May 20th, 2020
May 19th, 2020
Recent changes
Update April 2nd, 2020
Check the Play Tab for ongoing and upcoming tournaments.
You can also see ongoing and recent tournaments in Leaderboards->Tournaments
Many thanks to @GDII for the new styles and tournament calculations!
.
- Faster painting of positions on the board
- Move and other animations use native CSS transitions (was JQuery)
- Initial page load optimizations (speed, direct access to game in url)
- Other client optimizations
This should help a lot for users on slower computers and mobile phones.
4PC now supports 21 different Fairy Pieces. Check the Edit Position tab.
Sample game: https://www.chess.com/4-player-chess?g=3044931-0
Remember you can Shift-Click on any piece at any time to see its legal moves!
.
Use keyboard shortcut 'K' to toggle the coordinate helper (mouse over squares), or 'L' to toggle the coordinates.
Update Jan 28th
4pc now offers new possibilities for regular chess variants, such as King of the Hill + 3check combined, antichess + KotHill combined, etc
- Rando: make random moves.
- Ranter: on each move, 50% chance of playing either a random or a comfuter move
- Comfuter: regular comfuter
- Patzer: will play the worst comfuter move
- Pusher: Pushers are Comfuters that will always push pawns if possible.
- Checker: Checkers are Comfuters that will always check if possible.
- Muncher: Munchers are Comfuters that will always capture.
All zombies do not like to capture pieces of other zombies (except randos/ranters)
In addition, you can set zombies to be immune, meaning their pieces cannot be captured. These are like moving walls, very powerful pieces!
Update 16 January, 2020
Switched to a simple and fast connection library, 4pc now handles sockets/rooms/observers itself. Hopefully connections will be more reliable and faster.
You can now open 4pc in multiple tabs/windows. Shift- or Ctrl/Cmd- click on games (in the watch/archive list, or on 'Playing/Observing' in a player-popup or friends list) to open them in a new tab.
Rules changes:
This is an attempt to discourage teaming from A-Z in high level FFA.
FFA/Solo: King captures take priority over checks or pins by the player whose king can be captured.
After Green moves the Knight, Red can capture the Blue king (as long as Red is not in check by another player as well). Similarly if the red bishop were pinned by a blue piece, it would be allowed to capture the king.
Solo: Autoresign: If there are only two players left, and one of them cannot win (there aren’t enough points left to be made to reach 1st), the he is forced to resign. This prevents “king making” (deciding the winner) by a player who cannot win himself.
More changes:
New Game Modes:
The quest for fun modes continues, especially for an FFA that not be so teamy.
“+3” was inspired by Hest1805: checkmates/kings are worth 3 points (rather than 20). Resigned kings will sit still (no DeadKingWalking, as in the old days).
"Takeover" (FFA/Solo)
When you checkmate a player, his pieces (but not pawns) join your army! If a player resigns, their pieces remain live (worth points, but don’t move) and can still be taken over by checkmating their wandering king.
“Play-4-Mate” is a game where only checkmates matter. No points for pieces! And: the first to deliver a checkmate will win the game (+60 points), but further checkmates matter (+30 and +15 points for 2nd/3rd checkmate), a total of 105 points each game, and rating changes will correspond to how many points a player made. 105-0-0-0 is much like a solo win, 60–30-15-0 much like FFA.
Back to 1|15D default for Solo, time control settings no longer saved separately for solo/ffa/teams.
Support for 2- and 3-Player games: You can create 2- or 3-player games by creating a custom starting position where one or two players are dead. Thus these games can only be played casual, unless admins decide to list such games. The rating system now supports 2 and 3player games. They count as variants.
Team-engines:
@Tony and @omatamix have each developed a 4-Player Teams engine, and can invite players to play against their bots: @TeamTerminator1&2 and @PhoenixZero1&2. Games may be rated as long as the same engine plays both sides of a team.
Faster updating of online friends, up to 200 friends checked.
Fixed:
- Solo rating deflation.
- Solo-antichess games ending when resigned army stalemates.
- Discovered checks counting double in N-check Games.
..plus tons of fixes, improvements, and new features..
Update 8 October
(Solo is Free-for-All, but only the winner gains rating, 2nd-4th lose equally.)
For Leaderboard champions: Standard leaderboards count double, point chase and most games played no longer count.
Rule Changes:
For some variants such as N-Check, King of the Hill, Capture the King or DeadWall, sufficient mating material is defined differently.
Other notable changes:
LAG compensation: the time it takes to receive the last move and send a new move back to the server is added back to the player’s clock. It should now be possible to premove several moves per second regardless of your connection speed (ping).
Improved premove implementation
Antichess: opposite color bishop endings end the game (insufficient material)
Analysis board: 3-fold repetition is now detected in variations
Invite partner button in bottom left corner after closing game-over window (and for archive games)
If you click on ‘Playing’ in a player-popup or the friends tab, the board will be rotated to that player when the game loads. Same for ’Observing’ if the player played in the game.
Comfuters will move more quickly (3s max)
You cannot add or remove antichess rules from listed custom games. (You can, but you can't keep it rated)
Update 15 July
Rule Change:
• New FFA resignation mechanics: upon resignation or timeout, before the pieces turn grey, the king will try to make a (random) move. If he can't move, he will sit still. (So, a resigned king won't be stalemated right after a resignation. And he won't capture his own pieces to escape on that move. But on the next move he can capture grey pieces to escape, as it was earlier.)
Other notable changes:
• Fixed Teams rating range bug when accepting invites.
• Added Teams invite restrictions to prevent sandbagging abuse.
• In N-Check games, lives are now taken into account when checking for 3-fold repetition.
• Typing "33.", "24.b" or "move 29" in chat will create a link to that move, just like "#123456" will create a link to game 123456.
Update 21 May
Rule Changes:
New Features:
Before you join a queue, make sure you read and understand the rules! (see List of variants) Also pay attention if a game is rated or casual. As soon as 4 players join a game, it will start (and the 4 players leave other queues they joined). The number in the top left corner shows how many different players have joined at least one game (and will drop by 4 each time a game starts). The list is sorted by number of players joined, so games will rise up as players join. Games you joined will always be at the top of the list.
- You can't invite players you block or players that blocked you. (you can now close aka ignore invites)
- Blocking currently has no effect on chat or anything else in the 4pc app.
- If you are blocking (but not blocked by) players upon joining a queue, you are shown the username of the player(s) you blocked (so you can consider unblocking).
Fixes and Improvements:
Update 22 January
As before, autoclaim only happens when claiming does not change the standings.
See https://www.chess.com/clubs/forum/view/claim-win-and-autoclaim for details on autoclaim.
Update 13 January 2019:
Update 5 January 2019:
Update 17 December 2018:
Fixed:
Enjoy!