Show HN: Black Ops II Statically Recompiled To Native ARM64 macOS

A developer has released bo2-mac, a beta project that statically recompiles the Windows version of Call of Duty: Black Ops II into a native ARM64 macOS app using the player’s own Steam copy. The project reports that campaign play, solo Zombies and multiplayer matches against bots run on a base Apple M1 without Windows, Wine or a virtual machine, though the results come from the developer’s own tests and have not been independently confirmed.

The repository, posted as a Show HN project and dated November 3, 2026, translates the game’s three main executables: campaign, Zombies and multiplayer. Its stated pipeline lifts functions from 32-bit x86 machine code into LLVM intermediate representation, applies project-specific rewrites, then produces ARM64 code. A custom runtime supplies Windows interfaces, while its Direct3D 11 layer renders through Apple’s Metal.

The developer reports testing on one Apple M1 with 16 GB of memory. Campaign performance was 51–60 frames per second, solo Zombies generally ran at 57–60 fps, and multiplayer against bots reached 53–60 fps. The developer says every campaign mission loaded and advanced to the end credits, but clarifies that the campaign was not played through from beginning to end in the reported test. Die Rise, a Zombies map, ran at 43–58 fps.

The project says conversion takes about one hour and 45 minutes on an M1, with campaign available after roughly 45 minutes. Peak disk use is reported at about 10 GB, falling to about 4 GB after conversion. The repository says it contains no game files: the tool checks the user’s executables against the expected Steam build, asks the Steam client whether the signed-in account owns the game, and builds the app locally.

A New Route to Mac Play

If the reported results hold up, the project offers a different route for running a Windows game on Apple Silicon. Rather than translating instructions while the game runs through a compatibility layer or virtual machine, it converts the executable code ahead of time and links it with a Mac runtime. The developer reports that the game runs as native ARM64 code in a single process, with only certain untranslated or copy-protection sequences handled by a small x86 interpreter.

That approach could matter to Mac players because Black Ops II was not released for macOS, and the project says existing options have not made it practically playable on Apple Silicon. The result remains a single-developer beta report, however, not a broad compatibility test. Performance, stability and the amount of work needed to support other Macs or game builds remain open questions.

The project also points to possible changes beyond performance. Its developer says split-screen support is in progress, describing it as a feature the PC version did not have. That work is not presented as complete, so the current release should be understood through the play modes and conditions tested so far.

How the Recompiler Works

Black Ops II was built for 32-bit Windows PCs, while Apple Silicon Macs use ARM64 processors. The project addresses that mismatch by translating the game’s machine code before launch. Its account describes Ghidra cataloguing functions, Remill version 6.0.1 lifting them into LLVM IR, and custom passes rewriting the resulting representation before compilation. A hand-written runtime implements the Windows imports the game uses, and a Metal-backed graphics layer handles Direct3D 11 calls.

The developer says about 150,000 functions are translated across the three executables. It also says gaps in the translation are intended to fall back to interpretation rather than make the game crash. The app opens through the game’s menus, and the project reports keyboard and mouse input plus DualSense support through Apple’s GameController framework.

The repository identifies itself as an unofficial fan project and says it is not affiliated with Activision, Treyarch or Microsoft. Its instructions require a purchased Steam copy and state that users must build their own app rather than share a ready-made version containing the game’s code.

““This repository contains no game files and no translated game code.””

— The bo2-mac repository

Limits of the M1 Test

The headline performance figures come from one base M1 system, and the repository does not provide independent testing across other Apple Silicon Macs. It also warns that screen recording reduced performance, particularly in the campaign. The reported frame rates should therefore be read as results under the developer’s stated test conditions, not as a guarantee for every machine or setup.

The project describes a beta and provides selected play tests, not a complete independent audit of compatibility, stability or the translation pipeline. It says the campaign was tested through mission transitions to the credits but was not played end to end. The source material does not establish performance in multiplayer against human opponents, online-service compatibility, or whether all possible game builds and configurations work.

It is also unclear how quickly the project will be updated if Steam changes the executables it accepts, or how much support will be available to users who encounter problems. The repository says it accepts only the exact Steam build it verifies, which may limit use to that version.

Testing and Split-Screen Work

The next evidence to watch for is testing beyond the developer’s M1, along with reports from users who can build the app from their own Steam copies. Such reports could clarify how performance varies by Apple Silicon model and whether the listed modes remain stable outside the recorded demonstrations.

The developer says split-screen support is in progress, but has not given a completion date in the supplied project description. For now, the available claims concern campaign, solo Zombies and multiplayer against bots under the stated test conditions; the project’s next release or documentation update may provide more detail about compatibility, known issues and planned features.

Key Questions

Does the project provide a copy of Black Ops II?

No. The repository says it contains no game files or translated game code. Users need their own Steam copy, and the tool builds the Mac app locally.

Which modes does the project report working?

The developer reports campaign play, solo Zombies on six maps, and multiplayer against bots across 11 game modes. The supplied results do not establish support for matches against human players.

What Mac was used for the performance figures?

The reported figures were measured on one Apple M1 with 16 GB of memory. They are developer-reported results and are not an independent benchmark across Mac models.

Does it run through a virtual machine or Wine?

The project says it uses ahead-of-time static recompilation and a custom runtime, rather than Wine or a Windows virtual machine. It says a small x86 interpreter handles some sequences the translation does not cover.

Is the project an official Activision release?

No. The repository describes bo2-mac as an unofficial fan project and says it is not affiliated with Activision, Treyarch or Microsoft.

Source: github.com