Demon/Hell Born Teemo

Nah, on the surface this sounds like a good idea but once you go deeper it really isn't.

Lets take a look at Teemo's character lore. On the outside he looks like a cute, friendly and cuddly yordle who just wants to be friends. However once he goes into battle mode he becomes a sociopathic killer with no hesitation or regrets. The oxymoron at play here really adds to his character. When you take away the oxymoron of a cute killer, it takes substance away from the character.

Also one of the most fun things to do to piss people off as teemo is to use his laugh. It is so high pitched and adorable that it increases the aggravation and frustration of your opponents. Changing it to a demon/hell born laugh would ruin it.

Or maybe have it so when he is in combat (with champions), to take on this form, and convert back, when out of combat? or in the bushes?

Bro this is TEEMO were talking about here, everyone is missing his most important feature that leads the enemy into rage quitting. What about his SHROOMS what would they look like? What say you?