OpenSummoners

An open-source reimplementation of Fortune Summoners: Secret of the Elemental Stone (Lizsoft, 2008 JP / Carpe Fulgur, 2012 EN Steam release).

This is an educational reverse-engineering and game-preservation project. The goal is a drop-in replacement for sotes.exe that behaves indistinguishably from the original for a user who owns a legitimate copy of the game.

Not distributed: no game assets, no decompiled binary code, no copyrighted content of any kind. You supply your own copy of the game (Steam).

Status

Early development — the port is not yet playable. The engine core boots and the opening arc (title → town intro → arrival cutscenes) already renders 1:1 against the retail exe, but a playable game is still a long way off. In the meantime the project ships two finished, usable tools — the resource explorer and the Japanese voice patch below.

Development detail: docs/STATUS.md (current front), docs/PLAN.md (roadmap), docs/PROGRESS.md (changelog).

Get the game (support the author)

Fortune Summoners is still on sale — if this project interests you, please buy the game and support Lizsoft:

• Fortune Summoners Special Edition (Steam, 2020) — published by Lizsoft directly; Japanese + English, Windows 10 fixes. Recommended, and the edition the voice patch targets.
• Fortune Summoners: Secret of the Elemental Stone (Steam, 2012) — the original Carpe Fulgur localization; the engine this port reimplements.
• The voiced Japanese release (the one that shipped the sotesx_s.dll voice bank) is out of print — see tools/ennse_voice/README.md for the exact edition metadata if you want to hunt down a second-hand copy.

Downloads

Every build is produced by CI and published to Releases — each ships no game assets (everything reads your own legitimately-owned files at runtime). The rolling nightly pre-release always carries the latest build; tagged vX.Y releases are cut at milestones.

Resource explorer — res_explorer.exe

A native viewer/exporter for every resource type in the game's files, decoding with the engine's own reverse-engineered code: maps render exactly as in-game (tiles + scenery + props + townsfolk, with per-cell/per-object inspection and debug overlays), sprite sheets (palette, colorkey, frame grid), sound effects and the 1,448-clip Japanese voice bank (waveform, seekable playback), BGM streams, string tables — plus hex/info views and PNG/WAV/WMA/JSON/TXT export, per resource or in bulk. Drop-in run: it auto-detects your install. Download the nightly build · docs: tools/res_explorer/README.md.

Japanese voice patch (EN Special Edition)

Restores Japanese dialogue voice to the English Special Edition (English text + JP audio) — something no official English release ever shipped. Install by pasting one line into PowerShell — it auto-detects your game + your JP sotesx_s.dll and installs; re-run to uninstall. The exe is not modified. One-liner + manual zip: tools/ennse_voice/README.md.

The port — opensummoners.exe

Drop it beside your Fortune Summoners install. Early development (see Status); today it is a developer artifact, not a way to play the game.

Getting started (NixOS / WSL2)

nix develop
./tools/setup.sh         # symlinks game into vendor/, runs Steamless, hashes binaries

This enters a dev shell with the full RE toolchain (Ghidra, radare2, mingw-w64 32-bit cross-compiler, Frida, Pillow/numpy/scikit-image, …) and prepares the game files for analysis.

sotes.exe is Steam-DRM packed — the entry point lives in a .bind section appended by the SteamStub wrapper. tools/setup.sh runs Steamless to produce a clean vendor/unpacked/sotes.unpacked.exe that Ghidra can decompile directly.

Layout

docs/         design notes, file-format specs, progress log, engine quirks
src/          our C reimplementation (cross-compiled with mingw32)
tests/        unit suite + scenario harness (golden BMP + audio/input traces)
tools/        setup, build, extract, capture, contact-sheet, ghidra-headless,
              Frida agent + capture driver, Job-Object launcher
vendor/       game files (gitignored) — symlinked from the user's Steam install
              + Steamless-unpacked sotes
ghidra/       Ghidra projects (gitignored — derived from the original binary)
runs/         test artifacts (gitignored)

Workflow

Heavy use of a Frida-based harness against the retail exe for ground-truth probing, with hidden-window + turbo + silent-audio defaults so a harness run never disrupts the desktop:

• Hidden window + turbo from day 1 — the agent rewrites ShowWindow → SW_HIDE, virtualises timeGetTime, and no-ops Sleep, so the engine ticks as fast as the host can churn through it.
• MessageBox auto-dismiss in both the harness (Frida-side hook) and the drop-in (dev_hooks.c patches user32!MessageBoxA/W to log → IDOK). A blocked modal dialog never silently stalls the run.
• Job-Object launcher wraps every .exe spawn so a SIGKILL on the WSL side atomically tears down the Windows-side game process — no stray processes after a botched run, ever.
• Bit-exact frame diffs between retail and our re-impl (once the DDraw7 surface-lock hook lands), with red-tint overlay on mismatch.
• Input trace sparse JSONL format the harness replays into both targets for deterministic side-by-side runs.

The harness grows into a TAS bot that drives a whole game session at inhuman speed, exercising different subsystems against retail and our re-impl in lock-step.

Sibling projects

OpenSummoners is the third in a series of sibling RE projects, each distilling lessons from the last:

• openrecet — Recettear (the first; reference for hard-earned conventions)
• OpenMare — Patrician III (newer, refined workflow — the closer model for OpenSummoners' shape)
• OpenSummoners (this repo) — Fortune Summoners

Cross-references & credits

OpenSummoners' reverse engineering is cross-checked against independent community work — most notably the Fortune Summoners Fan Discord (invite) and their SotES Data Formats & Values spreadsheet, which documents struct layouts, enums, addresses, and data tables for sotes.exe. Our thanks to that community for their preservation work.

Their spreadsheet is consulted as a cross-reference / lead, not as ground truth: every fact a port depends on is independently re-verified at the byte level against the decompile + a host test before it is relied upon (the same discipline applied to our own subsystem survey). Where our function-level RE 100%-proves something the spreadsheet is missing or marks uncertain, we publish a human-verifiable proof others can reproduce — see docs/ods-crossref.md and docs/proofs/.

License

MIT. See LICENSE. The license covers OpenSummoners' own code only; no rights are granted to the original game.