Wishes of Tomorrow is a full-length Pokémon ROM hack for the Game Boy Advance — an original region, cast, and three-act campaign built at source level on RHH's pokeemerald-expansion 1.15.3, itself a C and ARM decompilation of Pokémon Emerald. Nothing here is patched into a prebuilt binary: every map, system, and asset is compiled from source, so the engine is part of the deliverable rather than a black box the game sits on top of.
Status — content complete and play-tested. All three acts run end to end, followed by a scripted finale, an original credits sequence, Hall-of-Fame save integration, and a post-game chapter. The full campaign and post-game have been played through and verified.
| Languages | C (ARM7TDMI / GBA), ARMv4T assembly, GBA event-script assembly, Python 3, JSON, GNU Make |
| Toolchain | arm-none-eabi-gcc 14.2.1 and agbcc under WSL2; parallel Make builds; the gbagfx / mapjson / jsonproc / aif2pcm asset pipeline; mGBA 0.10.5 for instrumented testing |
| Content tools | Porymap (maps and event authoring), Porytiles, Poryscript, LibreSprite, VGMTrans (NDS sequence extraction) |
| AI-assisted development | Claude Code as the primary implementation surface — engine work, cutscene scripting, asset pipelines, and build verification — with Claude Design and Claude Cowork for planning and iteration |
Scale, measured as a diff against the upstream base: roughly 82,000 inserted lines across 3,434 files. That breaks down to ~9,000 lines of C and ~4,900 lines of headers implementing engine and gameplay systems, ~33,500 lines of event-script assembly driving cutscenes, dialogue, and quest logic, ~15,800 lines of JSON map and encounter data, and ~2,400 lines of Python tooling. The result builds to a 32 MB cartridge image.
Custom engine systems written for this project include a Shadow Pokémon capture-and-purification framework — snag mechanics layered onto the ball-throw path, per-species persistent logging with idempotent save-forward backfill across party and PC boxes, battle-side stat modifiers, and summary-screen status indicators — plus a quest journal with deferred toast notifications, a visual-novel character portrait system bound to a speaker-name table, an HM field-move menu that removes the need for dedicated HM carriers, animated boss intro cards, and a set of scripted-cutscene primitives (detached camera objects, audio-suppressed screen shake, weather and SE muting, pooled particle effects).
Custom tooling: 30 purpose-built Python utilities. The largest is a tileset compiler that converts raw RMXP-format art into GBA-legal primary/secondary tileset pairs within the hardware's 512-tile, 7-palette budget. Alongside it: a sprite-import pipeline that colour-merges, quantizes, ground-line-aligns, and indexes 64×64 battle art against vanilla frame geometry, and an NDS-to-GBA music staging pipeline used to import 25 sequenced tracks and 461 direct-sound samples.
Content shipped: 64 new maps, 34 new tilesets, 277 new graphics assets, 12 tracked quests, and original trainer rosters and wild-encounter tables spanning the region.
- An original region and a three-act story campaign, from a quiet mountain village through a surveillance city to a finale atop a tower — with an archipelago of post-game islands to surf and fish between.
- The Shadow Pokémon system. Corrupted Pokémon fight harder and defend worse, and can slip into Hyper Mode mid-battle. Steal them from enemy trainers with the Snag Machine, then purify them to keep the offensive edge without the drawbacks.
- Snag Balls — a custom ball with a heavy multiplier against Shadow Pokémon, sold on the black market.
- The Shadow Log, a dedicated field menu tracking every Shadow Pokémon in the game as loose, snagged, or purified, with completion counters for post-game collection.
- Quest journal with a start-menu interface, main and side quest tracking, and on-screen notifications as objectives advance.
- Character portraits during story dialogue, driven by a speaker table so any named NPC can be given a face without touching a script.
- Boss encounters with animated intro cards, custom teams, and scripted set-piece choreography.
- Quality-of-life systems: an HM menu that frees a party slot, custom heal locations and checkpoints, a curio shop for Mega Stones, and Ability Machines.
- Custom soundtrack, sequenced and ported from later-generation Pokémon titles into the GBA's m4a engine, with the mixer widened from 5 to 12 direct-sound channels so field effects survive a busy score.
- A post-game chapter with a legendary encounter, a personal transport system, and a liberated overworld that reflects the ending.
- Built on
pokeemerald-expansion, so the modern battle engine comes along with it: current-generation Pokémon, moves, abilities, items, and battle gimmicks. SeeFEATURES.mdfor that full upstream list.
Wishes of Tomorrow — a game by Joe Maloney. Story, direction, game design, map design, and event scripting.
Sprite Design Rafael Sanna · aveontrainer · baylorhernandez · biadoxaf · DarkusShadow · jaov46
Character Art ToxShadows642
Shadow Sprites pogokitten · WeeGeeDude · Quanyails
Tileset Art pinkscales · Phyromatical · MagiScarf · PeekyChew · Elinthind · lo8jd · Dark Slayer
Shin-Tokyo Art Emeiry · Odisea by ekat99 — used under CC BY-NC-SA
Battle Backdrops carchagui (open sea, cave, and the FR-patch Lab/Space/Town/Indoors) · aveontrainer (Ashlands savanna, molten summit)
Music Arranged from the Pokémon soundtracks.
Playtesting Luke Devereux · Mike Mancuso · Kyle Clarkson
Special Thanks The spriting community, and every artist who shares their work.
Rest in Paradise, Connor.
A Flatfoot Games project.
This game is built on RHH (ROM Hacking Hideout)'s pokeemerald-expansion, and would not exist without it or the decompilation it stands on.
Based off RHH's pokeemerald-expansion 1.15.3 https://github.com/rh-hideout/pokeemerald-expansion/
- RHH —
pokeemerald-expansionand its full contributor list - pret — the
pokeemeralddecompilation project - Pokémon Emerald Version — GAME FREAK · Nintendo · The Pokémon Company
Third-party asset attributions carried over from the base are listed in EXTRACTED_ASSETS_CREDITS.md.
This branch holds the game. The main branch is the development workspace behind it — separate history, published alongside it:
- Source art — sprite sheets, Shadow Pokémon battle art, UI mockups, raw tilesets before they were compiled
- The tileset pipeline — the Python that converts RMXP-format art into GBA-legal primary/secondary tileset pairs
- Design documents — the GDD, story canon, quest plans, the full encounter spreadsheet, and a running development log covering every feature and engine gotcha (contains story spoilers)
- The music porting process — how later-generation tracks were sequenced into the GBA's m4a engine
Reuse terms differ by asset — most of the art belongs to the artists credited above, not to this project. See Reusing this work before taking anything.
❗ Do not use GitHub's "Download ZIP" option — it omits commit history, which is required to merge upstream updates.
Build instructions, toolchain setup, and update guidance live in INSTALL.md. In short, from a WSL2 or Linux shell with devkitARM installed:
make -j8This produces pokeemerald.gba, playable in mGBA or any accurate GBA emulator.