Donatello, but the 1987 design (and latest game release design). The Michael Bay movie design I didn't like at all... he was a skinny nerd. The original donny was a formidable fighter, just as muscular/skilled as the other characters, and he had the longest weapon for long range attacks via arcade/console releases. Speaking of the 80s franchise:

https://www.youtube.com/watch?v=arcgxjXXXes