Space is littered with monsters of different species and colours - in each level you must collect all the monsters requested by mission command (shown at the top of the screen) before the fuel runs out. Each level gets faster, with more variety in species and colours and more monsters on screen at once.
Tapping a monster that is not required will smash it into your ship and waste valuable fuel - occasionally fuel barrels will fly past which you can tap to top up your fuel.
Had these monster graphics from vector stock lying around, they were already prepared for another project that never got off the ground, so I thought I’d put them to good use!
https://github.com/otterstudios/Space-Monsters
http://www.youtube.com/watch?v=jJd5ymL5UYs
