Defilak was a matoran who used to be really dumb, having been fired from his job after running over a random matoran. He got a job as a scholar and became smarter than all the ko-matoran in all of Mahri nui. He can speak French, Japanese, Chinese, Italian and sign language. Defilak is a skilled inventor, traitorous, nervous and arrogant. He has a bad temper, once beating up a random Toa of air because he called him a squid. He does not trust anyone with anything, including the bank so he carries all his money with him.