I need help beating turn 4

[Codek]

1 or 2 spiders most of the time are alive. No tanks ate the POX debuff. The SCH died first then WHM from Knights and Soldiers aggro though now that I think about that, it might have been due to the OT not getting aggro on both right away. Should the healers be in the North West corner to avoid immediate aggro?

The first dread is long dead at the end of wave 3.

Ya, sounds like the OT (assuming War) just needs some practice with grabbing adds that phase. Generally, I will stand in the center to butch block the one that drops in the middle and spam tomahawk on the south side. Having healers in the North West can buy some extra time and avoid getting interrupted by the adds.