PC98PC-98/PC-88 · 1998 · Touhou bullet-hell shmup

Touhou 4: Lotus Land Story

3 projects: matching decomp, AI-assisted decomp, agent environment.

Projects

AI-assisted decompREA (16-bit DOS support), agentic27 starspushed 2026-10-12MIT license

Source reconstruction of 東方幻想郷～ Lotus Land Story

Builds MAIN.EXE/OP.EXE/MAINE.EXE/ZUN.COM from maintained source; goal: run full game (native builds need not be byte-exact)

ReC98 (TH04)covers 5 games

Matching decompTurbo C++ 4.0J, TASM/TLINK, master.lib, Tup; runs on PC-98 emulators…876 starspushed 2026-03-16no licenserelease P0335

The Touhou PC-98 Restoration Project

TH04: 46.62% reverse-engineered, 39.30% finalized, 100% position-independent (status as of 2026-01-19). MAIN.EXE 34.07% RE; 100% PI allows modding. Lead dev nmlgc announced retirement on 2026-07-10 (blog 2026-10-05) citing AI 'vibecoded' f…

thrl (Touhou Reinforcement Learning Framework) + th98patchgeneral tool

Agent environmentDOSBox-X (pc9821) + ReC98-debloated patched builds (th98patch: stage/…3 starspushed 2026-10-12GPL-3.0 licenserelease v0.2.3

Touhou Reinforcement Learning Framework

Active (2026-10); paper 'A High-Fidelity Reinforcement Learning Environment and Baseline for Multi-Objective Bullet Hell Games' (Zenodo 10.5281/zenodo.21788472). Also a headless Taisei simulation (touhourl/taisei-sim).

What you need

You need your own copy of the game: these projects ship code only.

Agent environments

touhourl/thrl (via th98patch)

Same toolchain

GameMethodYearStarsLast push

PCCounter-StrikeDecompAI-assisted decomp+520002.8k2026-10-11 PCTouhou 8: Imperishable NightMatching decompDecomp+320041052026-10-12 PCTouhou 10.5: Scarlet Weather RhapsodyMatching decompAI-assisted decomp+12008572026-10-02 ARCNBA JamSource releaseRE candidate1993972023-10-18 WIIKirby's Return to Dream LandStatic recompRE candidate20111672026-09-17 NESMike Tyson's Punch-Out!!ReimplementationDisassembly+11987462020-09-13 SNESSuper Mario KartStatic recompReimplementation+31992142026-10-08 PCTouhou 7: Perfect Cherry BlossomMatching decompAI-assisted decomp2003562026-10-11

More on PC-98/PC-88

GameMethodYearStarsLast push

PC98Uncharted Waters: New HorizonsReimplementation19931342026-10-02 PC98Touhou 5: Mystic SquareMatching decompAgent environment199812026-08-23 PC98ThexderDisassemblyRE candidate198532026-07-07 PC98ZeliardDecompAI-assisted decomp198762026-08-20 PC98DōkyūseiReimplementation1992162022-04-24 PC98SnatcherReimplementationDisassembly198882026-10-05 PC98RustyStatic recompRE candidate19932026-10-10 PC98Touhou 3: Phantasmagoria of Dim.DreamMatching decompAI-assisted decomp199722026-10-08

Found via morluto/rea, rec98.nmlgc.net/, rec98.nmlgc.net/blog/2026-10-05, touhourl/th98patch, codeberg.org/thrl/thrl

GitHub data checked 2026-10-12. Notes are summaries from the research pass; the project pages are the authority.