Sartharion has 2,510,100 health in 10-man.
Originally Posted by Stern
Vesperon grants him an additional 25% health bringing that to 3,137,625
Divide that by the amount of time you have to kill him (About 80 seconds iirc), which means you need ~39220 Raid DPS.
Divide that by the number of DPS (8), and everyone needs ~4900 DPS.
If you factor in the tank, you could probably get away with ~4700 DPS.
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