SNK put Mutation Nation on Neo Geo in 1991, while the hardware was still building its reputation as the most powerful arcade board you could also own at home. It is a side-view brawler in which you fight through the streets of a city overrun by mutated creatures.

The genre was peaking at that moment. After the big arcade beat 'em ups of the late eighties, every publisher wanted a variation on the same structure: move left to right, clear the screen, meet a boss. Mutation Nation layers mutation onto that formula as an art direction, which means enemies that transform mid-fight and a deliberately grotesque cast.

Neo Geo was well matched to the job. Generous sprite capacity and a wide colour budget meant characters could be considerably larger and more detailed than on contemporary consoles, and the game could keep several enemies on screen without the frame rate collapsing.

SNK's distinguishing trick was that arcade and home versions were essentially the same software: the AES cartridge ran what the MVS cabinet ran. The price of the home system, however, sat far beyond most players' reach, so a lot of this catalogue only reached a wide audience much later through emulation.

OldGame.cz carries a profile with screenshots and release information. If you are surveying early-nineties arcade brawlers, Mutation Nation is a representative look at the genre just before it started to fade.