I ran across a Blue slime wearing a strange hat that I didn't have yet. So I attack it and killed the first cube, only to notice I didn't get any new hat. Confused, I look for the second slime to see if he was wearing the hat. After a quick scan to see where he plopped I found the hat. To which I panicked, due to it being on a creeper standing right in front of me.
Yes, the hat wearing creeper looked like a hat on a giant blue slime.