There's a funny bug with the missiles when Blocky Man is killed and doing the death animation. When this happens, the missiles will hit Blocky Man during the death animation, causing him to bob back up. With the rate that the missiles fire, it constantly keeps Blocky Man afloat. This isn't the first time I've encountered this bug, but this time made me laugh quite a bit to see. I wish I could take a short video. Luckily, the bug is very easy to fix, so it's nothing to worry about.
For the missiles, I was originally going to add SDL_gfx support to do sprite rotation, and do a little trigonometry to calculate the angle between Blocky Man and the missile. Naturally, I thought this was an overkill, and stuck with the basic implementation. Anyway, I don't think anything else in the game will use sprite rotation, so there really isn't a need to add SDL_gfx support.
Next up are the Robot Overlords. I've got some big plans for these enemies, but the hard part is implementing those plans. I'll just say this: they're big, invincible, and very powerful[evil]