For agents
Games that make good reinforcement-learning and agent environments, because the code is open enough to run headless, read state directly, and step faster than real time. Curated by hand; claims about speed and determinism come from each project's own README.
All 442 games with an existing agent environment
Agents can read the registry directly: /api/games.json lists every game, each game has a full record at /api/games/<slug>.json, and /llms.txt explains both.
RL-ready today
An RL environment or agent harness already exists, and the game's code is available (decomp, recomp, reimplementation, or official source).
GameMethodYearStarsLast push
GBPokémon Red/Bluepret/pokered disassembly (full RAM symbols in .sym); sp00nznet/pokemon recompiles it to a headless native DLL that runs PWhiddy's agents with no emulatorEnvironments: PokemonRedExperiments, pokemonred_puffer, PyBoy envsMatching decompAI-assisted decomp+419967.9k2026-10-12GBAPokémon Emeraldpret/pokeemerald decomp, plus native SDL and WASM ports that run headless without an emulatorEnvironments: PokeAgent harness, pygba, PkmnRLArenaMatching decompDecomp+320043.6k2026-10-12GBPokémon battles (Gen 1 to 9)pkmn/engine re-creates the Gen-1 cartridge battle code and is over 1000x faster than Showdown; Pokémon Showdown is the open simulator for later generationsEnvironments: poke-envMatching decompAI-assisted decomp+419967.9k2026-10-12GCSuper Smash Bros. Meleedoldecomp/melee is 100% matched and has native PC ports; melee-sim-light claims about 120k frames/s headless with a batched NumPy APIEnvironments: libmelee, slippi-ai (Phillip), ssbm_gymMatching decompDecomp+320012.4k2026-10-12N64Super Mario 64100% decomp; libsm64 exposes Mario physics as a library, sm64-binds makes the whole game a steppable and cloneable library, and sm64coopdx supports 16 players with a Lua APIEnvironments: sm64-AI, mario64-RL-unityMatching decompStatic recomp+419968.9k2026-10-11PS1Crash Team Racingnative C port from the decomp (ctr-native / Turbocharged)Environments: CTRRl: Gymnasium env that runs headless and faster than real time, with a 66-float observationMatching decompAI-assisted decomp+319993942026-10-12APL2Prince of Persia 1/2SDLPoP source port from the disassembly; quickerSDLPoP2 is a thread-safe single-header game coreEnvironments: Principia, PoP_RL, JaffarPlusSource releaseStatic recomp+419896.9k2026-10-11PCTouhou 6 / Touhou 4–5th06 matching decomp, plus th06-headless, a deterministic sim faster than real time; TH04 is rea's showcase reconstruction; ReC98 covers TH01–05Environments: th06 RL agents, touhou-pc98-rl, thrlMatching decompReimplementation+220026132026-10-12DOSDoom / Heretic / Hexenofficial id/Raven source; Freedoom provides free assetsEnvironments: ViZDoomSource releaseMatching decomp+8199320k2026-10-12PCQuake III Arenaofficial source (ioquake3); OpenArena provides free assetsEnvironments: DeepMind LabSource releaseReimplementation+319998.3k2026-10-10PCStarCraft: Brood WarOpenBW reimplementation runs much faster than real timeEnvironments: BWAPI, TorchCraftMatching decompDecomp+219981.7k2026-10-06DOSCommand & Conquer / Red AlertOpenRA engine; EA released the original source under GPL in 2025Environments: OpenRA-RL (2026, on PyPI)Source releaseReimplementation+3199618k2026-10-11PCHeroes of Might and Magic IIIVCMI reimplementation; an HoMM3 matching decomp is about 99% doneEnvironments: vcmi-gymMatching decompReimplementation+119995.9k2026-10-12PCSlay the Spire 1 & 2Java (StS1) and Godot/C# (StS2) code is easy to decompile; sts_lightspeed is a C++ simulatorEnvironments: CommunicationMod, sts2-rl-agent (about 28k steps/s)ReimplementationReadable bytecode+120195202026-10-12PCBalatrothe whole game is plain, seeded Lua; jackdaw-balatro is a bit-exact Python reimplementationEnvironments: BalatroBot, BalatroBenchReimplementationReadable bytecode+12024772026-09-26PCCelesteFNA/C#; Everest mod loader; CelesteTAS adds frame-advance and savestatesEnvironments: celeste-rl (about 2,600 FPS)Source releaseReadable bytecode+120184.0k2026-10-09PCTrackMania Nations ForeverTMNF-C: deterministic physics in C with CUDA vector envs; trained inputs reproduce the same times in the real gameEnvironments: TMNF-C, tmrlMatching decompReimplementation+120087472026-09-30PCRocket LeagueRocketSim reimplements the physics, about 20 minutes of game time per second per threadEnvironments: RLGymReimplementationAgent environment20152522026-05-16WEBgenerals.ioopen rules; generals-bots is a JAX simulator running over 10M steps/sEnvironments: generals-botsReimplementationAgent environment20161242026-10-10NESSuper Mario Bros.full disassembly, C/Kotlin ports checked over 250k+ frames (SuperMarioBros-C, SMB-Vanilla), nesrecomp buildEnvironments: gym-super-mario-bros, stable-retroSource releaseMatching decomp+719853.2k2026-10-07MDSonic 1/2/3/CD/ManiaSonic Retro disassemblies, RSDK decomps, mstan segagenesisrecomp native buildsEnvironments: stable-retro (OpenAI Retro Contest)Matching decompDecomp+619913.6k2026-10-11ARCStreet Fighter III: 3rd Strike3s-decomp and the 3SX native C portEnvironments: DIAMBRA Arena, MAMEToolkitMatching decompSource port+119993472026-10-12PCStardew ValleyC# with the SMAPI mod APIEnvironments: StarDojo (NeurIPS 2025)DecompNative port+220162.8k2026-09-28DSMario Kart DSAI-assisted decomp plus a recompEnvironments: gym-mkds and about 7 othersMatching decompDecomp+32005622026-10-10PC3D Pinball Space Cadetcomplete decomp; open-cadet supplies CC0 table data, so no Microsoft files are neededEnvironments: earlier pinball RL agentsMatching decompDecomp+219954.7k2026-08-15Headless sims carved out of decomps
Game logic pulled out into a library or headless core. These are the cheapest way to get millions of steps, and the strongest new pattern in the 2026 data.
GameMethodYearStarsLast push
WIIMario Kart Wii: Kinokoheadless reimplementation of the physics; replays all 55 real ghost tests frame-for-frame. No RL wrapper exists yet.Matching decompStatic recomp+520081.1k2026-10-12N64Ocarina of Time: libootOoT gameplay from the decomp as a library: headless, deterministic, several instances per processMatching decompStatic recomp+419987.4k2026-10-12PCCrimsonland: crimsonpip-installable Python version checked tick by tick against the original (RNG, float rounding); about 64% matching decompMatching decomp20031872026-10-12NESNES Tetris: meta_nestristhe NES Tetris rules in Rust with Python bindingsStatic recompReimplementation+319892822026-09-30X360Skate 3: skatecore-cppthe skating mechanics as a dependency-free C++ library, alongside skate3recompStatic recompReimplementation20101.6k2026-10-11N64Wetrix recomprecompiled into a linkable game libraryMatching decompStatic recomp199822026-09-30NESArkanoid: arkbot / Excitebike: exciteBotexact C++ reimplementations of each game's physics, built for searchReimplementationDisassembly19842026-08-15PCPvZ-Emulatorfast Plants vs. Zombies simulator with Python bindings; PvZ-Portable and re-plants decomp alongsideMatching decompDecomp+520091.2k2026-10-122600JAXtariabout 67 Atari 2600 games reimplemented in JAX, with no ROMs neededEnvironments: JAXtariMOBClash Royale: Hasty-CRdeterministic, integer-exact simulator with a PPO agent and a live-game bridgeEnvironments: Hasty-CRReimplementationAgent environment20163722026-10-10DOSDaggerfall decomp100% matching decomp with a headless driver (fallplay.py)Matching decompReimplementation+119963.5k2026-10-07PCRise of Nations: attrition / donheadless, integer-only sim that stays frame-for-frame in lockstep with the original; don is a reimplementation built as an RTS agent envDecompReimplementation200322026-10-11Multi-agent & self-play
Fighters, arena shooters, party and sports games with built-in bots or local multiplayer.
GameMethodYearStarsLast push
N64Perfect Darkdecomp-based PC port with Linux and netplay; built-in simulants (up to 80 in Dab's mod)Matching decompSource port20008692026-10-12N64GoldenEye 007decomp hit 100% in Aug 2026; goldeneye-pc-port on Linux; the Sightline fork has a headless determinism harnessMatching decompStatic recomp+119977972026-10-10N64Super Smash Bros. 64100% decomp; BattleShip native port boots straight to versus, with CPU level 9 as a baseline opponentMatching decompStatic recomp+219994752026-10-12SNESBomberman 64 / Super BombermanN64Recomp and snesrecomp builds with deterministic headless hosts; 4-player battle works like PommermanStatic recompDisassembly19931092026-08-26N64AKI wrestling (No Mercy, WM2000, VPW2, …)six recomps on one engine (jessetbh), so one wrapper could cover all sixMatching decompStatic recomp2000272026-10-12WIIMario Strikers / Strikers Charged100% decomps with native Linux ports; 4-player soccerMatching decomp152024-06-13GCMario Party 4100% matched (USA); about 50 minigamesMatching decompStatic recomp+220028642026-10-12PCCounter-Strike 1.6 stackReGameDLL_CS + ReHLDS reverse-engineered server, Xash3D engine, YaPB bots: 5v5 with a headless serverSource releaseMatching decomp+319984.4k2026-10-12OTHHalo: Combat Evolved (OpenCE)matching decomp feeding OpenCE; Linux, WASM, 128-player netcodeXBOXDead or Alive 3 / Tekken 3 / UMK3playable recomps or decomps of 2-player fighters; UMK3 iOS has all 2,572 functions decompiledMatching decompStatic recomp2001112026-10-12PCDuck Game Rebuilt / TowerFallrebuildable C# decomp of a 4-player arena; TowerFall's towerfall-ai mod for agentsEnvironments: towerfall-aiDecompAgent environment20141952026-06-26OTHCall of Duty 4 MP / Unreal Tournament 99recomps whose built-in bots fight over LAN; UT99 sp00nznet recomp has --headlessLong-horizon strategy & management
Deterministic sims with big state spaces; most run headless already.
GameMethodYearStarsLast push
DOSOpenTTD (Transport Tycoon)headless dedicated server, null video driver, AI scripting, admin portEnvironments: OpenTTD AI APIReimplementationDisassembly+119958.4k2026-10-12PCOpenRCT2 (RollerCoaster Tycoon 2)headless server, JS plugin API, deterministic simReimplementationAgent environment200216k2026-10-12PCTotal Annihilation100% matching decomp (Byte Tactics) plus the Recoil/Spring engine with headless AIMatching decompStatic recomp+219977032026-10-12PCCiv III / SimCity 2000 / RA2 / Tiberian Sun / Theme Parksp00nznet pcrecomp builds with built-in headless modes; recomp-harness-mcp lets agents run about 90 of themGBAAdvance Wars 1/2/Dual Strikeheadless native recomp plus decompsMatching decompStatic recomp+12001762026-10-10GBAFire Emblem 8near-complete decomp and a playable recompMatching decompStatic recomp+120042252026-10-12PCFreeciv / Uncivopen source 4X gamesEnvironments: CivRealm, CivAgentSource releaseReimplementation+119962.2k2026-10-12PCFallout 1/2, Diablo, Caesar IIIfallout-ce, devilutionX, Julius: faithful, complete portsMatching decompReimplementation19982.5k2026-10-03DOSSyndicatedeterministic per-step core checked against the original for 3,851 turns; about 63% matching decompMatching decompReimplementation+21993162026-10-11PCWarzone 2100 / Seven KingdomsGPL code and free data; built-in AISource release19994.0k2026-10-113D worlds & racing (frontier difficulty)
Long-horizon 3D control and exploration. Mostly decomps with native ports, with no RL wrappers yet.
GameMethodYearStarsLast push
N64Zelda: Ocarina of Time / Majora's Maskmatching decomps, Ship of Harkinian / 2Ship ports, Zelda64Recomp's hook and mod APIMatching decompStatic recomp+419987.4k2026-10-12PS2Jak & Daxter 1–3OpenGOAL native builds; a live REPL can read and change any game objectDecompSource port+220013.6k2026-10-09GCTwilight Princess / Metroid Prime / Pikmin100% (TP, Pikmin) and about 99.8% (Prime) decomps with native ports (Dusklight, Metaforce)Matching decompSource port+120065.8k2026-10-11N64Mario Kart 64SpaghettiKart port with a track editor, plus an N64Recomp buildEnvironments: gym-mupen64plus (emulator baseline)Matching decompStatic recomp+219962.4k2026-10-11N64F-Zero X / F-Zero GXG-Diffuser port (30 racers, course editor); GX decomp built by AI agentsMatching decomp19982802026-10-01N64Top Gear Rally100% byte-exact decomp; native port already runs headless from scripted inputMatching decomp199752026-10-09ARCOutRun (Cannonball) / wipEout rewritesmall, fast C/C++ racing codebasesEnvironments: Cannonball DQN projectSource releaseReimplementation+219868792026-10-11PS2Gran Turismo 4decomp at 72% of functions; Tourist Trophy decomp tooMatching decompStatic recomp+12004442026-10-12PS2Burnout 3sp00nznet recomp with --headless and scripted pads (2–4 fps for now)Matching decompStatic recomp+120041872026-10-09PS2Sly Cooper / ICO / Dark Clouddecomp-based ports on Windows and Linux; Dark Cloud is 100% matching with random dungeonsMatching decompReimplementation20022702026-10-11PS2GTA San Andreasgta-reversed runs headless on Linux with function hooks (re3/reVC were DMCA'd)ReimplementationAgent environment20042.6k2026-10-12X360Sonic Unleashed / Sonic '06UnleashedRecomp and MarathonRecomp (XenonRecomp)Static recomp20085.2k2026-09-29LLM-agent & turn-based
Discrete, legible state. A good fit for language-model agents and planning research.
GameMethodYearStarsLast push
ARCZork I–III + Infocom canonMicrosoft relicensed Zork I–III as MIT in Nov 2025; historicalsource has about 30 Infocom sourcesEnvironments: Jericho / TextWorldSource release197832021-10-14GBCPokémon TCGpret/poketcg complete disassembly; turn-based card duelsMatching decompDisassembly19983292026-10-06PCYu-Gi-Oh! (ygopro / Forbidden Memories)ygopro-core runs every card as a Lua script; native Forbidden Memories port built from the decompEnvironments: ygo-agentReimplementationAgent environment19994232026-10-09GBAPokémon Mystery Dungeonpret pmd-red/pmd-sky decomps plus a static recomp; procedurally generated dungeonsMatching decompStatic recomp+120052842026-10-09PCGame mods that expose MCP toolsa 2026 wave of mods exposing game state as MCP tools (e.g. STS2MCP); search GitHub for '<game> mcp'ReimplementationReadable bytecode+120265122026-10-07Tools for agents
For games without a project yet. Both work on games you own; neither ships game data.
reaAn MCP server that lets an agent drive Ghidra, IDA or Hopper to reverse engineer native, DOS, .NET, WebAssembly and Android binaries.GitHubuniversal-modderA plugin for Claude Code, Codex and other coding agents: skills, tools and a shared knowledge base for modding PC games you own. MIT licence.GitHub