Hydrolaze maybe you are using a too small number to spawn enemies, remember that every second has 30 frames so for every spawn you have to count to 30*how many seconds you want them to spawn
Great for a first game. You could improve the graphics (except the laser boss, that one is freaking awesome), especially the background, it looks like we're flying over a carpet :P
But overall it's really good Ill give a 4.
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