Why Ornn seems busted as heck.
Okay, first of all, this is just my opinion and you can feel free to leave your opinions in the comments.
First off, from what we see in the trailer, he seems broken in general and even at this point, I still can't think of much counter play against him. He has an ability that can increase the duration of stuns, meaning that tenacity is essentially useless at this point. Not just that, but also an ult that can change directions, like really? This is so useful in team fights, for two reasons. The first is that it's an easy way to dish out damage and even cc the entire enemy team. The next is that, even if you are able to dodge it just changes directions and comes at you again, meaning that you'll probably have to pop flash, and at that point the entire team is basically separated. But, that's not even the most broken part about him. He can also break through user generated terrain with his dash, meaning that Anivia wall, Taliyah wall, etc. will essentially be useless against him. But, I don't think that's where he shines. His passive is the most interesting thing to me, and probably the strongest. For one, he can "craft" items for his teammates, and gives them buffs (which we don't know of yet). That might not stand out to some people but, giving your whole team a buff, is actually really useful, as you can easily out scale the enemy team (which if you didn't know, is really helpful).
TLDR; Ornn is busted