I have literally never seen this keystone used, and I can't think of anyone who'd benefit from it.
I personally am not even interested enough in it to go try it out in practice mode, because it just seems boring.
Does anyone use this? Is there a champion its good on? Has anyone ever seen it in a non-troll game where people are actually trying to win?
Legitimately curious, no bullshit. All jokes aside. Serious as a heart attack, not trying to be a douche.
Edit: Another question... does Chilling Smite proc the ice ray or whatever?