Stable enough for a small server. Please report any issues. Currently supporting 1.14-1.18 with less tested 1.8-1.13 support.
Test server with bufferless alerts: test.grim.ac
GrimAC is an open source anticheat designed for 1.18 and supporting 1.14-1.18 with half working 1.8-1.13 support. It is free while in beta. It will be sold for $20 on SpigotMC and other various websites, without obfuscation, DRM, subscriptions, or other nonsense that plague other anticheats. Geyser players are fully exempt.
Discord: https://discord.gg/FNRrcGAybJ
Here are the main cores that make grim stand out against other anticheats
- We have a 1:1 replication of the player's possible movements
- This covers everything from basic walking, swimming, knockback, cobwebs, to bubble columns
- It even covers riding entities from boats to pigs to striders
- Built upon covering edge cases to confirm accuracy
- 1.13+ clients on 1.13+ servers, 1.12- clients on 1.13+ servers, 1.13+ clients on 1.12- servers, and 1.12- clients on 1.12- servers are all supported regardless of the large technical changes between these versions.
- Order of collisions depends on client version and is correct
- Accounts for minor bounding box differences between versions, for example:
- Single glass panes will be a + shape for 1.7-1.8 players and * for 1.9+ players
- 1.13+ clients on 1.8 servers see the + glass pane hitbox due to ViaVersion
- Many other blocks have this extreme attention to detail.
- Waterlogged blocks do not exist for 1.12 or below players
- Blocks that do not exist in the client's version use ViaVersion's replacement block
- Block data that cannot be translated to previous versions is replaced correctly
- All vanilla collision boxes have been implemented
- All movement checks and the overwhelming majority of listeners are run on the netty thread
- The anticheat can scale to many hundreds of players, if not more
- Thread safety is carefully thought out
- The next core allows for this design
- The anticheat keeps a replica of the world for each player
- The replica is created by listening to chunk data packets, block places, and block changes
- On all versions, chunks are compressed to 16-64 kb per chunk using palettes
- Using this cache, the anticheat can safety access the world state
- Per player cache allows for multithreaded design
- Sending players fake blocks with packets is safe and does not lead to falses
- The world is recreated for each player to allow lag compensation
- Client sided blocks cause no issues with packet based blocks. Block glitching does not false the anticheat.
- World changes are queue'd until they reach the player
- This means breaking blocks under a player does not false the anticheat
- Everything from flying status to movement speed will be latency compensated
- The player's inventory is tracked to prevent ghost blocks at high latency, and other errors
- All systems are designed to be highly secure and mathematically impossible to bypass
- For example, the prediction engine knows all possible movements and cannot be bypassed