The nova is no problem thanks to hand of freedom/emancipate, but the icebolt is a stun so I can't really avoid it (plus he does it almost constantly sometimes, where I get about a second of freedom before he goes ahead and does it again.) Right now the fight looks like it'll take most of the ten minutes (although I don't know how bad his enrage actually is), so inevitably I get iceblocked followed immediately by DnD at some point before the end.
But I'm only 87 right now, so I guess I'll finish leveling and try again.