Quote Originally Posted by Blackdawn06 View Post
Can someone explain why Bosses, and particular mobs, become immune to debuffs at certain times? For instance, demon wall during his second set of floor AoE, lasting until not too long after repel, and the last boss starting a couple seconds before first catastrophe lasting until after its cast... I cant put anything up on them. I had to deal with it a lot during Coil T2 as well. I cant find whats going on anywhere.
You can only refresh a DoT if you have equal or greater buffs/debuffs.

If you cast Bio with Raging Strikes, and then Raging Strikes falls off--You have to wait for Bio to fall COMPLETELY off before you can re-apply it.

The other thing that may be causing problems is Foe Requiem, which is a Bard song, and applies the same concept as above.