criticalmass 1:1.0.2-2 (ppc64el binary) in ubuntu hirsute

 criticalmass, aka critter, is a shoot-'em-up in the style of Galaxian with
 very colorful and smooth graphics (provided that you have 3d acceleration)
 .
 Note: criticalmass uses OpenGL, and will probably not run well if you do
 not have a 3d accelerator which is supported by X.