Ok, this was (definitely) the quickest piece I've made until now. I hadn't had any time during the week but I really wanted to enter this challenge since I've never made any animations before, always giving myself excuses, so the weekly challenge was a great incentive for me. I really don't expect to win anything, considering that I didn't polish it at all, I didn't even revisit the frames and colors after seeing the final animation, there aren't enough frames and this isn't any original idea. But I'm actually very happy with the outcome, considering how quickly and loosely I had to do it.
It was intended to be a shot from a cannon or something like that, but I guess it turned out better as an explosion (except that it would be better if there was more smoke). I took a look at several Metal Slug sprites, but didn't use any as a reference specifically.
Critics are very welcomed!