OpenTyrian is a port of the DOS shoot-em-up Tyrian. Tyrian is an arcade-style vertical scrolling shooter. The story is set in 20,031 where you play as Trent Hawkins, a skilled fighter-pilot employed to fight Microsol and save the galaxy. This port is done by ZX-81.

Release notes:

Hi All,

OpenTyrian is a port of the DOS shoot-em-up Tyrian. Jason Emery generously gave the OpenTyrian developers a copy of the Tyrian 2.1 source code, which has since been ported from Turbo Pascal to C. The port uses SDL, making it easily cross-platform.

See http://code.google.com/p/opentyrian/ for details.

Tyrian is an arcade-style vertical scrolling shooter.

Enjoy,

Zx.

http://zx81.zx81.free.fr/serendipity/index.php?%2Farchives%2F467-Caanoo-OpenTyrian-OpenTyrian-ported-to-Caanoo-v1.1.html