Donatello is the brains of the Teenage Mutant Ninja Turtles: scientist, hacker, mechanic, inventor, and weapons specialist. He designs and manufactures all the tools, gadgets, armor, vehicles, and weapons in Turtles' arsenal. Donnie is a mutated anthropomorphic turtle with brownish green skin. His signature color is purple, most prominently featured in his purple mask. His weapon of choice is a bō staff which also converts to a naginata via a switchblade inside one end of the staff. Donnie is much taller and skinnier than his brothers. He also has a gap between his teeth and distinct brown-red eyes. When in combat or when being stealthy, he has whited-out eyes. he wears a purple mask where the tails of the mask are longer than any of his brothers, except for Raph's. His ninja gear consists of a strap over his ninja belt, brown knee and elbow pads, light brown bandages wrapped around his ankles, wrists and white bandages wrapped around his fingers. Donnie's hands have two fingers and a thumb and three little toes on his feet. He is quick to anger. He frequently gets frustrated when he can't accomplish a task. He can be defensive and argumentative, especially when his intellect is challenged. He has been known to lash out whenever someone messes with his inventions or experiments, but it's often verbal rather than physical. Donnie is overall a compassionate character and would support his family and allies anytime. He is a skilled scientist, engineer, and mathematician. Because of his genius-IQ level, Donnie tends to over-analyze, overthink, and over-complicate things, ultimately putting too much of a burden on himself and making bad decisions. Similarly, his social skills are slightly lacking. His nerdiness can sometimes get in the way of properly communicating and connecting with others. Early in the series, he had to make himself a flowchart in order to navigate interactions with April, a friend of the Ninja Turtles. When it comes to explaining complicated things, he sometimes forgets that others are not on his same intelligence level—leading to confusion and frustration for all parties.