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WatchCat

WatchCat

Netty-based anti-cheat for Paper 1.21.11. All rights reserved.

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Compatibility

Minecraft: Java Edition

1.21.x

Platforms

Links

View source Join Discord server

Creators

Details

Licensed ARR
Published yesterday

Watchcat

Server-side anti-cheat for Paper 1.21.11. By @Az7car.

Website: https://watchcat.gg Discord: https://discord.gg/2hPbabJ9jP

Features

Combat Detection (53 checks)

  • Killaura, AimAssist, Reach, Hitbox, AutoClicker, Triggerbot
  • Velocity, AntiKnockback, Criticals, BowAimbot, AutoShield
  • AutoTotem, AutoArmor, FastBow, MultiAura, ShieldBreaker
  • MaceSwitch, NoSlow, FastEat, FastHeal, KeepSprint
  • AimLock, Regen, SuperKnockback, WTap, Backtrack
  • PitchLimit, NoMiss, InvisibleAim, ReachMulti, CPSLimit
  • Delay, AutoBlock, Combo, DoubleHit, PerfectBlock
  • ShieldBlock, AutoWeapon, AutoPot, AutoPearl
  • ReachOverride, HitBoxOverride, NoHurtCam, AntiWeakness
  • AntiHunger, NoFire, NoPush, SmoothAim, RageAura
  • ClickPattern, TickShift, AutoSoup, AutoLeave

Movement Detection (44 checks)

  • Speed, Fly, NoFall, Step, Jesus, Spider, Glide, HighJump
  • BunnyHop, FastLadder, Phase, Blink, LongJump, ElytraFly
  • BoatFly, NoWeb, Strafe, SafeWalk, EntitySpeed, Derp
  • AntiVoid, Motion, Gravity, AirJump, FastFall, Collision
  • Prediction, TimerBalance, TimerAccel, Swim, Ascension
  • JumpCheck, VehicleSpeed, IceSpeed, SlimeBlock, WaterSpeed
  • LavaSpeed, WallClimb, Clip, YPort, SpeedLimit
  • AntiLevitation, DolphinJump, Sneak, PingSpoof, PacketDelay
  • NoDrag, NoJumpDelay, SpeedField, EnderPearl, AutoWalk

World Detection (34 checks)

  • Scaffold, FastPlace, InventoryMove, FastBreak, Nuker
  • AirPlace, Tower, ChestStealer, BuildReach, NoSwing
  • AutoFarm, AutoFish, AutoMine, InventoryActions, AutoTool
  • BlockInteraction, FastConsume, GhostBlock, RotationPlace
  • InstantMine, MultiTask, Direction, PacketOrder, RotationBreak
  • BreakPattern, ChestAura, AutoRespawn, FastDoor, Surround
  • PistonPush, AutoSign, AutoDoor, AutoBrew, AutoEnchant
  • AutoAnvil, BoatGlitch, ContainerSort, AutoSmithing
  • PickRange, ExpPickup

Mod & Injector Detection (87 checks)

  • BrandDetector, PayloadProber, TickTimerAnalyzer, BadPackets
  • Freecam, AntiAFK, Timer, MorePackets, InvalidInteract
  • Disabler, SkinBlinker, SpinBot, HeadRoll, NoRotateSet
  • Flight, AntiSwear, AntiFlood, AntiAd, Aimbot, GroundSpoof
  • XRay, Baritone, AutoCrystal, AntiAntiXRay, OreBot
  • NoRender, Trajectory, ClickTP, AntiInvis, Proxy
  • AntiAntiCheat, ScreenShare, PluginDetector, ClientSpoof
  • PacketMani, ForceOP, NoPitchLimit, AntiFirework
  • ResourceSpoof, NameSpoof, NoAttackCooldown, AntiCactus
  • AntiBerry, NoPortalOverlay, NoPumpkin, NoFireOverlay
  • AntiFog, NoScoreboard, AntiPotion, CrashPayload, ESP
  • Tracers, NoFov, NoBob, AntiBlind, TimeSpoof, AntiShield
  • BookExploit, NoWeather, AntiWDL, SoundPos, PacketSpam
  • AntiResourcePack, NoPotionLabel, AntiBot, Raid

Machine Learning Brain

  • 32-dimension feature vector (rotation deltas, GCD, click variance, acceleration, packet rate, velocity std/mean/trend, pitch entropy, convergence)
  • ONNX Runtime inference (in-JVM, no external dependencies)
  • Isolation Forest anomaly detection blending with heuristic scores
  • CSV training data export for offline model training

Punishment System

  • Shadow flagging with configurable confidence thresholds
  • Randomized ban wave execution (30min-6hr jitter)
  • Severity-based duration tiers: 30 days to permanent
  • Offense multiplier: 1st=1x, 2nd=2x, 3rd=4x, 4th+=permanent
  • IP bans alongside UUID bans
  • Unique 7-character alphanumeric appeal code per player
  • Non-deterministic scheduling to blind cheat developers

Architecture

  • Direct Netty pipeline injection (no ProtocolLib dependency)
  • Fully asynchronous check execution (off-main-thread)
  • 100% reflection-based, no Mojang-mapped dependencies
  • Maven build, Java 21, Paper 1.21.11
  • 218 checks total | 265+ Java files

Building

mvn clean package

Output JAR in target/watchcat-1.0.0.jar.

Configuration

Edit config.yml in the plugin data folder. Each check has:

  • enabled - toggle
  • severity - critical/high/medium/low (affects ban duration)
  • weight - contribution to confidence score
  • Check-specific thresholds

Commands

  • /watchcat alerts or /watchdog alerts - toggle alert messages
  • /watchcat stats or /watchdog stats - check performance statistics
  • /watchcat profile or /watchdog profile - detailed check profiling
  • /watchcat checks [category] or /watchdog checks [category] - list checks with status
  • /watchcat player <name> or /watchdog player <name> - per-player check state
  • /watchcat reason <player> <reason> or /watchdog reason <player> <reason> - ban a player with reason
  • /watchcat reload or /watchdog reload - reload configuration
  • /watchcat whitelist <check|all> <player> or /watchdog whitelist - exemption management
  • /watchcat report <check> <player> or /watchdog report - report a false positive
  • /watchcat banwave or /watchdog banwave - trigger manual ban wave

Dependencies

  • Paper 1.21.11 (required)
  • ONNX Runtime 1.26.0 (bundled via Maven shade plugin)
  • Java 21 (required)

License

All rights reserved. Not for redistribution without permission.