The Obsidian Sanctum is single boss instance located underneath Wyrmrest Temple in central Dragonblight. The instance features Sartharion as the primary boss with the addition of trash mobs and 3 other min-bosses. The other mini-bosses aka Drakes may be killed or left up. The more drakes you kill the easier

Sartharion is to defeat, however, leaving additional drakes up will provide you with better loot.

Lava Waves: Throughout the encounter, Lava Waves will spawn from either the left or right side of the platform Sartharion is on. The waves to the opposite side of the platform from where they spawn. If a player gets hit, they will take damage, get knocked back, and have a DoT placed on them. To avoid them, players should move in to the gaps created.
Sartharion’s Fire elemental Adds: Sartharion also summons Fire Elemental adds every 20-30 seconds in groups of 2-4 and need to be offtanked. After 30 seconds, or if they are hit by a Flame Wave, they will enrage gaining 50% more health and dealing 400% more damage. This enrage can be removed by hunter Tranquilizing Shot or rogue Anesthetic Poison. DPS should prioritize the adds over Sartharion.
The encounter is basically just a tank and spank with slight movement every once and a while.
In addition to his loot, Sartharion also drops the tier 7 gloves.
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