ESO Dread Cellar Trifecta (The Dreaded) Magplar POV

Group Setup
DK Tank: 2 Earthgore, 5 Turning Tide, 5 Saxhleel's Champion, and Master's Sword/Shield.
Warden Healer: 2 Earthgore, 5 Spell Power Cure, 5 Powerful Assault, and Master's Restoration Staff.
Magplar DPS: 2 Iceheart, 5 Bahsei's Mania, 5 Deadly Strike, and BRP Daggers.
Magblade DPS: 2 Iceheart, 5 Order's Wrath, 5 Medusa, and vMA Inferno Staff.

Tank POV:    • Vdc HM 2&3 boss   (second and final boss)

For this trifecta, we only cleared the first two side bosses to save time. The third side boss is very time consuming to clear and not really needed. A healer is highly recommended due to all of the incoming damage in each boss fight.

First Boss HM: Slow burn and focus adds every 10%. Barriers are recommended between each pillar phase as this is the most stressful part of the fight. The group should be ready to bash the boss at least once between each pillar phase, as she will pick a random player to pull and feed on. I recommend grabbing the fire side boss (orange crystal) at 20% to make execute easier. You can grab him sooner, but you may risk pushing the boss too hard and getting extra adds.

Second Boss HM: Group should build up ultimate going into this fight. Activate the orange crystal at the start and push the boss as low as possible before the red waves appear. When the waves are out, focus on avoiding them. Roll dodge during the skull mechanic. When the skull mechanic ends, finish nuking the boss before the red waves reset.

Final Boss HM: Push the boss to 65% while clearing scamps with AOEs. Have a strategy for the red lines mechanic: one player can go backwards, another left, and another right. The portals appear at 65% and 35% with different mechanics. After each portal, summon one of the side bosses to help clear scamps and push the main boss to 60%/30%. A scorion will appear on the white crystal side of the room that the tank should grab ASAP. I recommend killing the first one (at 60%) and then ignoring the last one (at 30%) and just nuking the boss. Save the orange side boss for last to make execute easier.