In DEFEM you control a little UFO using the mouse, blasting away in all directions. Although the game is a shooter, you spend most of your time avoiding your enemies, rather than tackling them head on.
Earn points by destroying enemies and collecting gems to create gem-combos. These combos upgrade your ship with shields, lasers, and more. The higher the gem-combo, the higher the score you get for collecting each gem.
Move the ship with your mouse.
P - pause / resume M - mute + / - - increase / reduce music volume F1 on title screen for HELP.