Sega's Altered Beast has a new free port for the Neo Geo

Developer Teo Tormo released a free, native port of Sega's 1988 arcade beat 'em up Altered Beast for the Neo Geo AES, MVS, and CD hardware today. The project adapts the original arcade code to run directly on SNK's 24-bit architecture, and the ROMs are available now on Tormo's itch.io page.

I think it's a genuinely cool port of Altered Beast, mostly because of the hardware crossover. Sega and SNK were massive arcade rivals in the late 1980s and early 1990s. Seeing a foundational Sega System 16 game running natively on the hardware that powered Metal Slug and The King of Fighters feels like looking into an alternate timeline.

System 16 meets the Multi Video System

The conversion makes technical sense when you look at the silicon. Sega built the original arcade version of Altered Beast on its System 16 board, which uses a Motorola 68000 main processor paired with a Zilog Z80 for audio. SNK built the Neo Geo MVS and AES around that exact same CPU combination two years later.

Tormo specializes in exactly this kind of translation. He has spent the last few years porting games like RoboCop, Super Dodge Ball, and ESWAT: City Under Siege to SNK's platform. These aren't emulators wrapped around a ROM. They are native code adaptations that rewrite the original arcade instructions to interface directly with the Neo Geo's custom graphics and sound chips.

Rise from your flashcart

Directed by Makoto Uchida, who would go on to create Golden Axe a year later, the original game became a cultural touchstone largely because Sega chose it as the North American pack-in title for the Genesis in 1989. The digitized "Rise from your grave" voice clip is permanently burned into the brains of anyone who bought a console that year.

Sega ported the game to almost everything available at the time, including the Master System, the Commodore 64, the ZX Spectrum, and the Amiga. NEC even secured a version for the PC Engine. SNK's hardware was left out entirely, which made sense given the Neo Geo's positioning as a premium arcade platform rather than a standard consumer console.

The optical option

The download includes files formatted for Neo Geo CD systems, alongside ROMs built for modern MVS and AES flash cartridges like the NeoSD and Darksoft. Neo Geo AES flash cartridges are notoriously expensive, often costing hundreds of dollars just for the board.

The Neo Geo CD was SNK's attempt to solve that exact pricing problem in 1994, swapping expensive ROM chips for cheap optical media. Today, an optical drive emulator in a Neo Geo CD is one of the most accessible ways to play on real SNK hardware, and having a ready-to-burn disc image makes testing homebrew projects much easier.

The Neo Geo homebrew scene has spent the last few years quietly building an impressive library of cross-platform arcade conversions. Tormo's work adds another major piece of 1980s arcade history to a console that was originally famous for being too expensive to own. The files are free to download, and they work in standard emulators if you don't have a physical Neo Geo sitting on your desk.