I have one concern with Ivern
And it involves bot lane.
From the looks of it, his passive means he won't need a clear. And that makes me fear for several junglers, because of one bad habit that top and mid laners have that might infect bot lane.
Bot lane might hug tower and not use their trinkets early.
This will make multi-member invasions seem tantalizing if the bot lane is just chilling at their tower. Why mid and top laners don't just drop their trinkets into the jungle entrance and then tower hug is beyond me (unless there's an enemy Blitzcrank?). But if bot lane does that, it's going to make Ivern players vulnerable.
Maybe muscle memory will play out and the bot laners will stay with him early anyway, but I'm worried it'll have a similar effect like with other champions (Soraka is one fine example, causing the occasional lazy ADC to stop dodging skillshots and expecting every hit to be patched up).
jungle, or anyone else who doesn't need a leash....though I feel that Ivern would be a much more scary person to be invaded as for jungler since I'm sure you cant use his "release" passive if you are in combat or I'm going to guess that attacking it probably stops the release progress.