The spider regens extremely slow so if things go bad just blur it and rezz/buff and try again. The first wave of adds is a bunch of little spiders that need to be ae'd. All adds on the encounter can be mezzed. Once first wave is dead it's just a burn fight with a ****** ae every so often thats a poison resist check so buff poison. The ae hits me about 1 in 4 with 550+poison resist. Three times during the fight you get three adds just mezz them and offtank them one at a time then back on named. The adds are not linked so if you want to not offtank them once they spawn mezz then blur after you move the named out of agro range. We just offtank them they don't hit very hard like 1kish on a silk class max hit. Usually we blur the named around 40% and med back to full cause our healers mana usually getting a little low. No need to kill the last set of adds until the named dead we just mezz them and burn named then kill the final wave. All the adds can root so be ready for that.