Here is how I think he works:
He does not have 1 hero ability and 1 evil character ability. He has one set of abilities, however some only trigger as a hero and some only trigger as an evil character (Since evil characters can't rescue and heroes can't block). This means that if you chose evil character and he was later converted to a hero, his ability would still work. However if you chose hero for him and he was converted to an evil character, due to heroes converting to evil characters not keeping their abilities I would rule that he does not keep his ability. (If he was later converted back to a hero he would regain his ability. But I can't remember what would happen if he was Evil first, converted to good and then later converted back to evil)