Like other posts have said, these CH themselves or other mobs you are fighting if they are aggroed on you. Was killing a bunch of bile mobs for quest item and one of these got tangled up in a pull of mine and I didn't realize it was CHing everything I was trying to kill.
This is one of Verants famous fake /con's in the game. My Beastlord is level 59, and this spider was hitting me and my pet between 200 and 350hp for each hit. I didn't stick around very long before running back to the zoneline. Now I read here they complete heal also.
Definitely not worth fighting in this zone if the rest of the creatures are like this. Although I didn't get a chance to fight anything else, but doubt I'll go back. I suppose if your in a group it *might* be ok, but definitely not solo. Even in a group I bet people would die quick.
65 BST and I (58 necro) duo'ed these yesterday. Alot of fun and great exp. Simply have the BST pet tank and have necro warrior pet attack it from behind to /bash and interrupt it's casting. It would get a CH off sometimes but no big deal just cast mind wrack to keep the BST's mana up to heal pet. Throw in an occasional lifetap to interupt as well.
Actual levels on these are 54 - 56. They start to CH at 40-50% health and the lvl 56 spider is immune to stun. Having a bard or chanter chain mez the lvl 56 ones when they start to cast is an easy way to avoid the CH as they have too much mana to easily drain.
60 Cleric said that these are immune to the stun portion of cleric stun spells but the DD still hit. Our pali didn't complain of any immunities to stun or many resists. Was able to interrupt them freqently without too many problems. Would say 12-14k hp.
Malarian Larvae is foraged, don't see any reason why this would drop them so it's possible that someone was invis or something running by and meant to drop it but instead traded.
These mobs also cast complete heal on them selves. One good thing about complete heal being nerfed is that when this spider "complete healed" itself, is only went up about 2 bubs of life. Had one complete heal itself 5 times in a row before it was full life again. Of course we were doing as much damage as we could to take it down. Guestimate that they have about 15k-17k hp.
CH is 10k, so if it does 2 bubbs then it would put this guy at about 25k, which seems about right with the ammount my dots do when I solo them, seems like it might be a bit more though, like 30k