Just my 2 cents on the fight (well..more like 8 or 9 cents)
Heals Heals Heals!!
Phase 1: Spread out 6 yards, his Caustic Slime will hit a few random raid members, with the Bile-o-Tron active, this will simply bring you to 1 HP if your over 10k HP. He will also occassionaly do a Massacre attack which will bring EVERYONE to 1 HP. Quickly heal above 10k HP.
Phase 2: After a few Massacre's the Bile-o-Tron will go offline for a short time, everyone must stack as the raid is no longer protected and his Caustic Slime will now kill you...and it hits BIG, fortunately, any raid member around when hit by this will share the damage. It's necessary for the entire raid to stack and it hits upwards of 280,000 damage.
So from a dps stand point, spread out 6 yards for phase 1, stack for phase 2. Easy.
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Heals, haha, your fucked...good luck
But, for progression purposes to see some HP coming off the boss; an option is to overload the raid on heals to a point where nobody is dying and every attempt or so switch a healer back to dps until we find a happy medium.
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Tanks:
Correct me if I'm wrong here, but I understand it like this. The main tank simply needs to be above 10k HP like everyone else. The boss hits very very hard but the MT still will not fall below 1 HP.
The boss will receive a "Double Attack" buff fairly often during phase 1. At this point the off-tank will taunt the boss and eat these 2 strikes that come in rapid succession....the off-tank is the ONLY raid member that must be topped off during phase 1 prior to and during the buff.
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Any other thoughts?