This miniboss can be pulled by running down the hallway on the right or he can be pulled by taunting him on the left, but he will bring all those adds with him if you pull him that way. It is safer to have your healer run down the hall to trigger the miniboss while the rest of the group finish the first packs of trash.
Kill him in the center of the first room you enter, you can trap players with Shadow Wave if it is pulled in the hallway.
If you hero the starting trash on Fortified weeks of high keys, you should have it back up for the first boss.
Trash to Agronox
Fel Strikes have a 30y range and can be outranged.
When Fel Strikes are going out, have your range spread out and do a /say when it targets them. This will eliminate the strafing out of your own and into someone else’s strike, especially on stairs where you can’t outrange it.
Bat fear can be outranged at 40y. You can also avoid pulling extra bats by staying on the right hand side of the hallway.
Avoid the green buff/debuff bubbles on fortified unless you have a personal, they hit quite hard.
You can skip the last pat pack before going up the stairs with a Rogue Cloak.
Some stuns and slows work on the adds.
For higher tyrannical, your group may want to hero when the second adds come out, as the AOE damage with the stacking Poisionous Spores hits harder later in the fight.
Poisonous Spores: Mages can Ice Block to remove higher stacks.
After you kill Gazerax, Thrashbite will automatically spawn. If you have not killed the imp add pack in the middle, the boss will spawn on top of those adds. You can pull the adds and boss, run out of the room and LOS which will cause the boss to reset and you can fight the adds without the boss.
Many classes can immunity Scornful Gaze which saves a bookcase and prevents books from being spawned. Ice Block, Turtle, BoP, Netherwalk, etc.
You can silence the books when they spawn.
You can easily move away from the boss when the books spawn so you will not be slowed when Thrashbite does his AOE.
Trash to Domatrix
If the tank tanks the orbcaster mob on the top of the ramp (being careful not to LOS), then range can stand below and the orb will fly over their head and not have to move for it.
The biggest issue here will be the poison while killing spider miniboss, as not all healers can dispel the poison and it hits quite hard on higher keys. If your healer cannot dispel poison, if you have another class that can dispel poison (Monk Detox, Paladin Cleanse Toxins, Druid Remove Corruption), dispel the tank on CD.
Save hero for the Hellblaze Mistresses (large adds) that spawn at 50%. This also allows you not to burn hero on pull if your group fails to get the guardian and/or imps down quickly enough.
You will want to watch the boss health carefully to avoid pushing at 50% when the boss spawns the Hellblaze Mistresses (the large adds) if you have a Chaotic Energy about to hit. The large adds can knock players out of the shield. If you still have those adds up when a Chaotic Energy hits, stun them (or knock them back if they get close to shield) so they can’t knock anyone out of the shield and kill them.
Warlock can banish one of the Hellblaze Mistresses. If you have someone wearing Sephuz, you can have someone cast a CC on the Mistress and have the warlock re-banish.
You can click on the Aegis of Aggramar to see how much of the shield is left.
The shield on high keys, especially tyrannical can be depleted if you don’t micromanage when you get in the shield. Avoid getting in until the cast has <1 sec on the timer then move immediately out. If the shield depletes, you can still use the area as your default stack point for healing by casting things such as Darkness, Spirit Link Totem, etc.
The shield reduces damage done by those in the shield by 90% and reduces healing by 75%, so there is no point in lingering in the shield to finish a cast.
Many classes can immunity Chaotic Energy, such as Turtle, Ice Block, etc.
If a non-tank accidentally clicks and picks up the Aegis of Aggramar, they can right click to remove the buff so the tank can pick it up.
Immunity classes can soak orbs before they reach the center.
Final note, if you have Demonic Upheaval going out as you kill the boss, you still need to run out and not be standing within the circle when it pops or it will kill you (but not count against the timer).