Acid rain needs to be taken from the list of spells that can be cast in Delera during Mabar. Several casters are using it to grief others and stealing their kills.
When you are in a raid group the groups of spawns are larger. Some casters like to seek out those groups, but do not join them. Instead, as soon as a large spawn occurs, they immediately cast acid rain.
Acid rain lasts for several seconds as an AoE. Thus their acid rain is the first to do damage and tag all the undead that spawn.
This makes it impossible for melees and others to get any drops, as melee first is not able to damage any monster for several seconds, then when they finally can, the acid rain has already tagged the monsters.
I was in a raid group today. We got haunted by several casters casting acid rain on everything that spawned around us. We moved to another instance. They followed. We moved to another location. They followed. In the end we just decided to stop because of these people.
So I plea for a removal of acid rain from the allowed spells in Delera's graveyard. A game should not get this annoying.