Maelstrom is a port of the original shareware game for the Macintosh.
It is a fast-action, high resolution (640x480) asteroids-like game,
with detailed graphics and original sounds.

This version uses the SDL (Simple DirectMedia Layer) which provides
faster graphics and better sound than the old X11 version.
SDL also allows the screen resolution to be changed to 640x480 when
Maelstrom is run in full-screen mode.

Homepage:
https://www.libsdl.org/projects/Maelstrom/
