User blog comment:GreenMoriyama/Izo, the Blizzard Prince/@comment-3391671-20160418084953/@comment-25235491-20160617200743

These are my 3 cents on the question, so of course if popular opinion doesn't consider that OP, well proceeed ahead.
 * P: It's just that there are so many things that scale up.
 * Level 1: 27 damage, 25% slow that decays over 2 seconds, every 13 seconds.
 * Level 18: 146 damage, 50% slow that decays over 2 seconds, every 8 seconds.
 * W:: 4 seconds of grounding is definitely long, I'd keep it to 2 seconds at all ranks (even then, you have 5 seconds of powerup every 13 seconds). Also, now I see it, refreshing Frozen Edge is redundant with the ultimate.
 * R: I'm on the side that says Field of Rime does enough. The activation alone is a 1250-range point-blank-AOE root, which is extremely strong, and on top of that there's a 15% permaslow in the area lasting over 14 seconds after it. So in sheer CC, it's super strong, and I didn't count Hoarfrost.
 * As for the detonation buff, I was talking about how the increase to the damage was kinda useless, as it was so little.
 * I wouldn't mean for you to change that, as that would take a toll on Izo's damage, but perhaps change the CC components of the ultimate. Especially the root. I feel that it's very very strong for it to be attached to a permaslow with %-health damage on top of that.