ZerillisZerillis is a rare level 46 elite mob who patrols around the altar surrounded by Shadowpriests before you take the first left turn towards Theka's area.
The boss is accompanied by some familiar adds which can be CC'd or dealt with immediately.
Antu'sulAntu'sul is the Basilisk boss in Zul'furrak, and is found by passing through the cracked area in the wall to the right upon entering Theka the Martyr's room.
The boss himself is in a cave surrounded by patrolling elite mobs. Clear all of them before engaging the boss, because you will want to fight him outside the cave. The boss already summons Sul'lithuz Broodling and Servant of Antu'sul, so dealing with additional adds is a real headache.
The boss will pull when a player gets too close to the cave. Allow the tank to be that player in order to avoid pulling on accident and losing group members early in the encounter.
Theka the MartyrTheka the Martyr patrols the area around the shallow graves. He is a quick fight but will cast Theka Transform and become immune to physical and shadow damage at 25% health for 30 seconds.
Witch Doctor Zum'rahWitch Doctor Zum'rah is the zombie raising boss in Zul'furrak, found in the next room past Theka. The boss appears as Neutral to all players until you cross into the room the Witch Doctor resides in with his cauldron and treasure chest.
The fight is healing intensive and involves numerous Zombie adds and totems. So long as totems and adds are managed without running out of healer mana, this fight should not stop your group's momentum.
DustwraithDustwraith is rare elite mob in Zul'Furrak, who is located near the pool that Gahz'rilla is summoned from.
The rare mob is accompanied by a few adds, which can be CC'd.
Shadowpriest Sezz'zizShadowpriest Sezz'ziz and Nekrum Gutchewer together are the final wave of the classic zerg, or stair event, started by releasing Seargent Bly and his companions from their execution cages.
Sergeant BlyAfter defeating Shadowpriest Sezz'ziz, Sergeant Bly's party remains. Before talking to Bly to start the fight, make sure to talk to Weegli Blastfuse to have him set the charges for the door. If you don't do that before engaging, you will have to fight him with the rest of the party and also lose out on being able to fight Chief Ukorz Sandscalp.
Bly's group has a standard comp with Bly being the tank. Focus on Murta Grimgut first as she's the healer. After her focus on Oro Eyegouge the caster, then Raven the melee and finally Bly.
Chief Ukorz SandscalpChief Ukorz Sandscalp is a 48 elite Sandfury troll located behind the door that Weegil Blastfuse (the Goblin from Searget Bly's party) blasts open.
Ukorz Sandscalp is accompanied by another Sandfury Troll, Ruuzlu (level 46 elite).
Hydromancer VelrathaHydromancer Velratha is in the courtyard where you summon Gahz'rilla. She has multiple abilities and with being tucked around the corner from the entrance it is easy to engage her earlier than expected and deal with her and adds. Be careful with engaging her and this will be a simple fight.
Gahz'rillaThis level 46 elite hydra is a summoned boss in Zul'furrak. The Mallet of Zul'furrak must be used on the gong to ring it and call forth Gahz'rilla.
Be careful to clear adds on the side of the pool closest to the entrance to prevent stray mobs from entering the boss fight.
Sandarr DunereaverThis rare is on the way out of the instance after Gahz'rilla. Make sure to take a quick look before zoning out. He is a simple boss as long as you pull him without adds.