EDIT: if you're having trouble with level 3 (and this should give you a general idea of how to play the game) see this gif:
https://twitter.com/dietzribi/status/856324475431903236
BTW you can beat almost the entire game like this:
https://twitter.com/dietzribi/status/856480596113182720
BUT I would recommend to try beating it also in the 'hard way' :P
Sorry if the mechanics aren't explained good enough, I didn't have more time :(
Made for Ludum Dare 38
Theme was "a small world"
will update later if i remember i have to sleep now (this game was made in 48 hours and i'm dead now)
Here's the LDJAM site page for the game for when voting starts
https://ldjam.com/events/ludum-dare/38/space-hummus