One more on the minimalistic theme. This game is a mix of Asteroids (the Atari classic) and the amazing SUPERHOT.
I've added a nice screen shake when something explodes. I've learned this with two talks that are totally worth watching: The Art of Screenshake by Vlambeer's Jan Willem Nijman and Juice it or lose it by Grapefrukt's Martin Jonasson and Petri Purho.
Also, tunning the mechanic was pretty interesting: how fast can the ships fly, fire rates, bot AI. Overall, it was a lot of fun.
Done in 1 day, using ugl.