How the hell are you supposed to kill regen spammers?

I'm on the 6th dungeon. The Wardens here spam a regen buff that makes any enemy heal back everything faster than I can hit them. Even if I get a full overcharged Warblade with a decent weapon, they just get two regen ticks in a row and instantly heal it all off. How are you supposed to kill enemies with excessive regen? I didn't see anything that would allow me to remove the debuff and there was no way to wait it out.

Related question: how the hell are you supposed to stop Haste spammers? The boss of the 6th dungeon keeps fucking cheating. He does an AOE attack for 75% of my team's HP even with everyone using defend. Then all his adds get to move right after, including one that gets to use Haste and then take 39746 turns in a row. He eats through all my Taunt turns and then ganks everyone before I can do ANYTHING.