Diamond Abduct Forsvar

The aliens have come back for revenge, can you defend your colony?

A small retro arcade style game, where you fight against alien creatures and collect their diamonds to raise your score. Nothing big, but I would love any form of feedback!

Controls, WASD to move/navigate menu, Space to fire/select, Shift to switch firing formation. Alt to fullscreen, and Ctrl with +/- for pixel perfect scaling.