What Happens After a Game Is 100% Decompiled

2026-09-29 · Explainer

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A headline goes around every few weeks now. Some beloved game has been 100% decompiled. The comments fill with people asking where the download is, and nobody ever quite answers.

Here is the answer, using six games that were all reported complete in the same stretch of 2026.

Five of them really did finish. One of them did not, and that one is the only one you can actually play right now. That inversion is not a joke. It is the most useful thing to understand about this whole category.

What "100% Decompiled" Actually Measures

Decompilation means rebuilding a game's original source code by hand, from the compiled binary, with no access to what the developers wrote.

The bar for calling it done is stricter than it sounds. A matching decompilation is finished when the reconstructed C code, fed through the original compiler with the original settings, produces a binary that is byte for byte identical to the game on the disc. Not equivalent. Not close enough. Identical.

That standard is why these projects take years, and it is also why you can trust the result. There is an automatic test. If your reconstruction of a function compiles to different bytes than the original, you got it wrong, and no amount of confidence changes that.

So "100% decompiled" means one specific thing. Every function has been rewritten as readable source that provably reproduces the original.

It does not mean anybody built you a PC version. Those are separate projects, sometimes by separate people, and one does not automatically follow from the other.

Our decompilation and recompilation explainer covers how this differs from recompilation, which is the automated approach behind most of the ports on our recompiled games list.

The Six Games, and What Each One Actually Unlocks

Read that table left to right and the pattern is clear. The completion column and the playable column have almost nothing to do with each other.

Tier One: Finished, No Port, None Planned

Super Mario Galaxy is the headline name, and its project is called Petari. The code is at 100% matched. The data section sits at about 80%, which is normal at this stage and is mostly the slower work of reconstructing tables and structures rather than executable code.

The part everyone misses is in the project's own README. It says, plainly, that the project is not meant to be an effort to create a PC port, and asks people to stop bringing it up in the repository and the Discord.

That is not the team being difficult. Decompiling a game and porting it are genuinely different jobs with different skills, and a team that spent years on the first one is under no obligation to sign up for the second.

You will see a name attached to a supposed Galaxy PC port in some coverage. We went looking for it and could not find any such public repository. We are not going to treat it as real until there is something to point at.

Star Fox Adventures is in the same position and is the more impressive engineering story. Its repository was created in February 2026 and reached 100% matched code across every category by late September. That is roughly seven months for a full GameCube game.

Its data is at 99.96% and the visible work right now is naming things. Recent commits are about identifying what individual game flags do by cross referencing the retail placement data. That is the unglamorous phase where a correct but unreadable reconstruction turns into something a human can modify.

So what does a completed decomp with no port actually get you? Four real things.

Mods that were previously impossible. With real source, you change behaviour rather than patching bytes. This is how randomizers, quality of life patches and full conversions get made.

A port becomes tractable for someone else. The hard part is done and it is done publicly. Anybody with the porting skills can now pick it up without repeating the years of reverse engineering.

ARM64 becomes possible. This is the part that matters for handhelds. Once a game exists as portable source, compiling it for a Retroid or an Anbernic is a build target rather than a research project. That is exactly how Dusklight ended up on cheap ARM hardware after Twilight Princess was decompiled, and it is why decomp projects eventually reach handhelds that emulation never will.

Preservation. The game now exists as readable source that survives the hardware, the disc rot and the company.

Tier Two: Finished, and Someone Is Already Porting It

Kingdom Hearts 358/2 Days is the most interesting of the six, and the one nobody put in a headline.

Its numbers are the strongest here. Code and data both at 100%, with all 306 modules of the European build rebuilding byte identical to the original. The project reports over 23,000 matched functions, with the remaining handful being library assembly that C simply cannot express.

The speed is remarkable. The repository was created in late June 2026 and hit those numbers by late September. Three months for a full Nintendo DS game.

And unlike the others, there is a port underway. A companion project is building a native PC runtime alongside the decompilation, and the split between them is deliberate. One repository stays focused on matching the original exactly. The other adapts that understood code to modern platforms, so the matching work never gets buried under platform specific special cases.

What runs today is genuinely early. The asset pipeline handles textures, UI graphics, fonts, models, skeletal animation, text and audio. The game's front end boots natively, from the logos through the title screen and menus to character select, with the real assets and timings. There is an experimental gameplay harness in one Twilight Town room, which the project describes as useful for bringing systems up rather than as a real mission or combat loop.

There are no releases. Not an early build, not a nightly. Zero.

So this is the honest state of the best positioned game on the list. A complete decompilation, a real port under active development, a menu you could take a screenshot of, and nothing to download.

Tier Three: Complete With an Asterisk

Two of the six need a footnote, and neither footnote makes the work less real.

Legend of Mana is 100% matched for the North American release only. Every module, the main executable and all seventeen overlays, rebuilds byte exact. The Japanese release is at about 94%.

That is a normal shape for a PlayStation 1 project, because regional releases are genuinely different binaries. A decomp matches one specific build. If you saw "Legend of Mana is 100% decompiled" and own a Japanese copy, the claim does not cover you yet.

Fire Emblem: The Sacred Stones is the one we can say the least about, and we would rather say that than guess.

There is no public progress tracker for it. The project's own progress site is offline and it has no entry on the tracker the other five use. What we can see is that its leftover assembly directory holds only a couple of low level files and no per function assembly, which is what a finished project looks like. It also describes itself as a disassembly rather than a decompilation, which is a related but distinct kind of work.

The other thing worth saying is that this project started in 2018. Whatever state it is in, it did not get there in September 2026. If it appeared on a list of recent milestones, that framing is wrong.

The One That Is Not Decompiled, and Is the Only One You Can Play

Halo: Combat Evolved was on the list we were sent. It does not belong there, and what is actually happening with it is better than the claim.

The tracker its own decompilation links to reports 5.92% of code matched. The project's fork describes the same work as 99.5% byte matching. Those two numbers are very far apart, only 121 of 833 units are registered in the tracker's report at all, and we cannot reconcile them from outside.

Here is what is not in dispute. There is a playable native port, and it ships a build for Android on ARM64. Linux, Windows and Android, rebuilt on every commit, with cross platform multiplayer. It is the only thing on this entire page you can install today, and it is the only one that runs on the kind of handheld most of our readers own.

We wrote it up separately in Halo: Combat Evolved's native Android build.

Sit with the contradiction for a second, because it is the lesson. The game with the weakest completion claim on this list is the one you can play on a Retroid tonight. The game with the strongest one, Kingdom Hearts 358/2 Days, has no download at all.

Completion percentage and playability are independent. A partial decomp plus someone determined to ship beats a perfect decomp with nobody porting it, every single time. We have run into this from the other direction too. When we covered the Spider-Man recomp projects, the most starred repository could not render a frame while a quieter one had a full installer.

So Should You Expect Ports From Any of These?

Honestly, treat it as unlikely in the near term, and be pleasantly surprised.

Here is what would have to happen. Someone with porting skills, not just decompilation skills, has to volunteer years of unpaid work. They have to replace every platform specific system the original game used, graphics, audio, input, saves, file access, with something modern. They have to do it knowing Nintendo issues takedowns in this space. And for the Wii and GameCube entries, they have to handle hardware features that have no direct modern equivalent.

Kingdom Hearts 358/2 Days is the one to watch, because that work is already underway rather than hypothetical.

For everything else, the realistic near term outcome is not a port. It is better mods, better romhacks, better tools, and a complete public record of how these games work. Those are worth having on their own.

Why 2026 Produced So Many of These

The old assumption was that a matching decomp took the better part of a decade. Super Mario 64 and Ocarina of Time set that expectation, and both were multi year efforts by large groups.

The timelines here break that. Star Fox Adventures went from an empty repository to fully matched in about seven months. Kingdom Hearts 358/2 Days did it in about three.

Part of it is tooling. The community now has shared decompilation frameworks, automatic difference viewers, and progress trackers that turn the work into something measurable and social. Part of it is that a lot of people learned how to do this over the last few years.

And part of it is the argument the scene is currently having about AI.

It is worth noting how differently two projects handled it. The Super Mario Galaxy team put an unusually direct statement in their README: they did not use AI for decompilation work, the acceleration came from new contributors, and AI generated decompilation output is rejected outright. They allow it for naming, cleanup and documentation only.

The Super Smash Bros. Melee decompilation went the other way and used an AI model to close out the last stretch of a six year project, which we covered in the Melee decompilation piece.

Both are defensible, and the reason both can be is the matching standard. Byte for byte verification does not care who or what wrote a function. Wrong is wrong and it gets caught automatically. That is a stronger quality control than most software has, and it is why this corner of the scene has handled AI better than the layers built on top of it. Our look at the recomp scene's AI problem covers where the verification runs out.

What This Means for Handheld Owners

Three practical takeaways.

Do not wait for a port that has not been announced. Nothing here except Halo has a download, and only one has a port in development. Buying hardware in anticipation is a bad bet.

Decomp news is genuinely good news, just slowly. Every completed decompilation is a game that becomes ARM portable in principle. That pipeline is real and it is why PortMaster carries decomp ports that cheap Anbernic hardware can run. It just takes years longer than a headline implies.

In the meantime, emulate. Every game on this list is playable on handheld hardware today through ordinary emulation. Super Mario Galaxy runs in Dolphin, covered in our Wii emulation handheld guide. Star Fox Adventures is a GameCube emulation target. Kingdom Hearts 358/2 Days is DS emulation. Fire Emblem: The Sacred Stones runs on anything that plays GBA games. That is not a consolation prize. It is the answer.

Frequently Asked Questions

What does 100% decompiled actually mean?

It means every function of the game has been rewritten as readable source code that, when compiled with the original compiler and settings, produces a binary byte for byte identical to the original game. That identical match is an automatic test, which is why a finished decompilation is trustworthy. It does not mean a PC version exists.

Does a decompilation mean a PC port is coming?

No. Decompiling a game and porting it are separate projects requiring different skills, and one does not follow automatically from the other. The Super Mario Galaxy team states explicitly that their project is not an effort to create a PC port. A finished decomp makes a port much easier for someone else to attempt, which is different from one being planned.

Is Super Mario Galaxy playable on PC now?

No. The decompilation reached 100% matched code, but there is no port and the team has asked people to stop raising the subject. To play it on a handheld today you use Dolphin, which runs it on capable Android and PC handhelds.

Which of these games can I actually play right now?

Halo: Combat Evolved, through a native port with Linux, Windows and Android arm64 builds. It is also the one whose decompilation completion claim is disputed, which is the running irony of this whole category. Every other game on the list needs emulation.

Is Kingdom Hearts 358/2 Days getting a PC port?

One is in development. The decompilation is 100% matched, and a companion project has the game's front end booting natively with real assets, plus an experimental gameplay harness in one room. There are no releases of any kind yet, so there is nothing to download.

Why do decompilations take so long?

Because every function has to match the original binary byte for byte, which means matching not just the behaviour but the exact code the original compiler produced. Historically that meant years. Better shared tooling has compressed it, with Star Fox Adventures reaching 100% in about seven months and Kingdom Hearts 358/2 Days in about three.

Do decompiled games run better on handhelds than emulation?

If a port exists, usually yes, because nothing is being emulated and the game can be compiled for ARM directly. That is how GameCube era Zelda ended up running on cheap Anbernic hardware through PortMaster. The catch is that only a handful of games have both a finished decompilation and someone willing to build the port.

Was AI used for these decompilations?

It varies, and projects are increasingly explicit. The Super Mario Galaxy team states they did not use AI for decompilation work and reject AI generated submissions, allowing it only for naming and documentation. The Melee decompilation used an AI model to finish its final stretch. The byte for byte matching requirement catches wrong output regardless of who wrote it.

Related Reading

• Decompilation and Recompilation Explained
• Recompiled Games List: Every Native Port by System
• Halo: Combat Evolved on Android Handhelds
• The Simpsons Game Recompiled on Steam Deck
• Every Decomp Port You Can Play on a Cheap ARM Handheld
• The Melee Decompilation and the AI That Finished It
• The Recomp Scene's AI Problem
• Can Android Handhelds Run Recompiled Games?
• Twilight Princess on a Handheld with Dusklight
• N64 Recompiled Games List
• Best Handhelds for Wii Emulation
• Best Handhelds for GameCube Emulation
• Best Handhelds for DS and 3DS Emulation

Project completion figures reflect the state of these community efforts as of September 29, 2026 and change frequently. Every port mentioned requires game files from a copy you legally own.