Prof. Booster is 5'13" and Kazuma is 6'0". That's the explanation.
So yeah any character six feet tall or above automatically gets an extra tile of height. It works like that in real life too (this is why there isn't any characters that are like 17 pixels high.)
(I'm on mobile so hopefully this is worded right and helps)
1st problem: It wouldn't be the damage function actually. NPCs don't continually check player collision and then run that function from what I've seen. Instead it just has a variable of how much damage should be dealt on...
Don't use MS Paint. Unconfigured it will do stuff like this sometimes (has to do with the bits in bitmaps or something I'm not knowledgeable in it).
I personally use Paint.net ( https://www.getpaint.net/ ) and haven't had color pallette errors when saving .bmps with it. Most other paint...