Apogee's 1993 DOS shooter Bio Menace hits the Amiga

Independent developer astair86 has released a free, native Commodore Amiga port of the 1993 MS-DOS action game Bio Menace. The complete three-episode collection, dubbed the Thrillogy, is available to download now on itch.io.

It is notable that Bio Menace never made it to the Amiga back in the day. The European computer market was absolutely swimming in 2D platformers in the early 1990s, but this particular Apogee Software release remained locked to PC hardware. Designed by Jim Norwood, the game runs on a licensed version of id Software's Commander Keen engine. You play as CIA operative Snake Logan, a guy with a prominent mullet who crash-lands in Metro City and has to shoot his way through a mutant invasion engineered by Dr. Mangle and Master Cain.

Kickstart 2.0 and 1MB of Chip RAM

The new port utilizes GPLv2 reconstructed source code paired with the official game assets. Apogee actually made the entire trilogy freeware back in December 2005, which makes projects like this much easier to distribute legally without worrying about copyright strikes on the art and sound files.

To run it on real hardware, you need an Amiga setup with Kickstart 2.0 or higher. It also requires roughly 1MB of Chip RAM along with some Fast RAM. The port handles John Carmack's original engine compression logic natively on the Motorola 68000 architecture. Getting PC games from this era running on Amiga hardware is always an interesting technical challenge. The PC relied on brute-forcing EGA graphics, while the Amiga used custom chips for hardware scrolling and sprites. Translating the Keen engine's specific software scrolling routines to play nicely with the Amiga's chipset takes serious effort.

The Apogee shareware model

The original game was distributed using Apogee's famous shareware model. Founded by Scott Miller in 1987, Apogee basically invented the episodic distribution format that dominated PC gaming before the CD-ROM era took over. The first episode, Dr. Mangle's Lab, was free to distribute on bulletin board systems and floppy disks. If you wanted the rest of the story, you had to call a 1-800 number and buy The Hidden Lab and Master Cain. This Amiga release bundles all three episodes together in a single download.

Backporting PC shareware classics to platforms that missed out during their commercial prime is a welcome project. The Amiga had plenty of great run-and-gun shooters like Turrican and Ruff 'n' Tumble, but getting a piece of early id Software tech running on the system fills a nice historical gap.

Plasma bolts and landmines

The game itself holds up reasonably well. It is slower and more methodical than something like Contra, focusing heavily on finding keys, rescuing hostages, and managing your limited ammunition. Snake Logan starts with a basic machine gun, but you can pick up temporary upgrades like plasma bolts and landmines to deal with the tougher enemies. The enemy roster is pure 1990s shareware weirdness, featuring everything from standard mutant grunts to giant green slimes and robotic sentries.