Heroic Portal Keeper Hasabel

Tank

• Position Portal Keeper Hasabel against one side of the platform. Move her to the other when Collapsing World is cast.
• Taunt off one another when the Reality Tear debuff expires, usually around 3-4 stacks.
• Maintain threat on all adds that spawn from the Transport Portal.
• Move out of the lines created by the Felstorm Barrage.

Healer

• Stand 30-35 yards away from Portal Keeper Hasabel in a group to avoid excess movement when Collapsing World is cast.
• Be prepared to top the raid after the Collapsing World cast and when Reality Tear expires on the tanks.
• Move out of the lines created by the Felstorm Barrage.
• Be prepared to out heal a substantial amount of incoming damage when a portal is empowered.

DPS

• As ranged DPS: Stand 30-35 yards away from Portal Keeper Hasabel in a group to avoid excess movement when Collapsing World is cast.
• As melee DPS: Follow the boss out of the large Collapsing World circle as she is dragged across the room.
• Focus down, crowd control and interrupt all adds that spawn from the Transport Portal.
• Move out of the lines created by the Felstorm Barrage.

Platform Players

• Tanks should always try and leave the main platform just after tank switching for the Reality Tear debuff.
• DPS should try and have some cooldowns available to quickly kill the mini-boss on each platform.
• Always allow the tank to engage the mini-boss first.
• On the Fire platform: Vulcanar - 90%
• Interrupt Flames of Xoroth & Unstable Portal.
• Move away from the Supernova explosion zones.
• On the Fel platform: Lady Dacidion - 60%
• Interrupt Unstable Portal.
• Stack underneath the boss to allow the healer to efficiently heal the Poison Essence.
• Attack and destroy the webbing around the player targeted by Felsilk Wrap.
• Healers should keep all players above 35% health to allow them to survive the initial Felsilk Wrap damage.
• On the Shadow platform: Lord Eilgar - 30%
• Bloodlust to kill the mini-boss as soon as possible.
• Interrupt Unstable Portal.
• Stack underneath the boss to be able to target him, as well as allowing the healer to efficiently heal the Corrupt damage.
• Dispel the Delusions debuff when you need to heal, otherwise keep it for as long as possible to benefit from the mana restore.

Source: Portal Keeper Hasabel Antorus Raid Strategy Guide - Guides - Wowhead