I know that Thresh is labeled as a support for a good reason, and that the ability power gained from his passive has a small affect on all his abilities save for his ultimate, but Thresh's Q has a neat mechanic to it. The minimum amount of damage Thresh can do with the passive of effect of his Q is equal to how many souls he has collected. What that means is that while it would be meager early on, the bonus passive damage from his Q could scale indefinitely, unlike the stats gained from his passive which soft cap. Not only will his first attack in a fight hurt, but late game, he can get 200+ bonus damage on each hit without "winding up" the attacks. Plus he throws his green lantern and doesn't afraid of anything.