The Cauldron

Heavy Attack

Tank: Block his heavy slam attack.

Dps: Dodge roll it if it is not on the tank. It should never reach you.

Noxious Release

All: Avoid his three slow-moving gas clouds (fired in succession in three directions). They are easy to sidestep but punishing if you do not.

Summon Globs

Dps: Kill Bile Globs first. If they reach the boss (who runs to the room's center when summoning), he consumes them for a large damage buff. Kill Gore Globs (ranged Discharge attackers) too before he can eat them.

Gore Rush

All: Interrupt his charge (Gore Rush) right after he summons Globs, or be run down, thrown to the ground, and immobilized.

Butcher (explosive anchors)

All: Move away from his explosive anchors. He does not move or attack physically while they are out, so there is no rush.

Iron Maiden

Dps: Free whoever is caged in Iron Maiden by damaging it. It kills them if ignored.

Upper Cut

Tank: Block Upper Cut. It knocks back and down otherwise.

Dps: Dodge roll if it is on you instead of the tank.

Explosion (tank positioning)

Tank: When she channels her large ground effect, move to its edge and hold there. She comes to you, giving you a new fixed position until she does it again.

Explosion (area effect)

All: Never stand in the area effect itself. It ticks quickly for high damage over time.

Lightning Traps

All: Watch your footing around the Lightning Trap circles she scatters around the room (they land in groups of four). The helper NPC Drathas periodically clears some, but do not rely on him. If you must cross one, shield and block through it.

Chain Pull

All: If pulled (usually the furthest player), Break Free immediately. It is only dangerous if a lightning trap sits between you and the boss, since you are dragged through it and killed.

Ranged Channel

Dps: Interrupt her ranged channel (targets whoever is too far away) immediately. An uninterrupted cast is almost always fatal.

Add Waves

Dps: Kill adds on priority at each spawn wave (about 75%, 50%, and 25%). They are mostly ranged, so interrupt channels and watch for their arrow-spray cone attacks. No more adds after the last wave.

Heavy Attack

Tank: Block his heavy attack. It has a slight frontal cleave.

Teleport Adds

Tank: Taunt the two mirror-image adds he spawns on each teleport (they do not move). Kill them before returning to the boss. He teleports more often below 25%, so stay on top of this.

Lava Spit

All: Avoid the raining lava and fireballs from Lava Spit. They burn where they land.

Explosion

All: Get out of, block, or precisely dodge roll his room-spanning effect right before it detonates. An unblocked, undodged hit is a near-guaranteed kill for a DPS or healer, and a large hit plus knockdown for the tank.

Fireball Light Attacks

All: Dodge or block his (and his adds') fireball light attacks. Each hit stacks a debuff that makes all further fire damage you take worse.

Channel Fire

Dps: Interrupt Channel Fire immediately. It deals stacking fire damage per second to everyone and deals more damage the longer it runs.

Conductive Oil Synergy

Dps: Pick up the Conductive Oil synergy and run it to a power module, then move close to Lyranth to ignite it. Each module destroyed triggers one wave of enemies, so coordinate how many you destroy at once (one at a time is safest, more if your group can handle multiple waves together).

Bone Colossus

Dps: Kill the Bone Colossus quickly. It has low health, but if it starts screaming and stretching its arms it drops room-wide meteors you need to keep moving to avoid.

Ogrims

Dps: Interrupt the Ogrims' chest-beating channel. It knocks people down and can chain into other damage if left alone.

Daedroth

Tank: Keep the Daedroth's flame breath facing away from the group.

Titan

Tank: Keep the Titan turned away from the group. It hits the tank with ground effects and heavy punches, otherwise it is low priority.

Xivkyn Archers

Tank: Taunt the Xivkyn Archers immediately. Untaunted, their damage-over-time arrows can wear a tank down fast. They cannot be chained, so reposition to grab them all.

Dps: Prioritize killing the Xivkyn Archers over everything else in the room.

Storm Atronachs

All: Move away from Storm Atronachs when they die. They explode on death.

Heavy Attack

Tank: Block his heavy attack. It has long range for a melee hit.

Dps: Dodge roll if it is on you instead of the tank.

Galvanic Charge (cleave)

Tank: Keep him turned away from the group at all times. His frontal cleave applies a stacking lightning damage-over-time effect to anyone caught in it, and if two tagged players stand together their effects stack and kill them quickly. Do not stack with anyone if you are tagged.

Fire Geysers

All: From 60% and below, avoid the Fire Geysers spawning under players' feet. A strong healer can carry you through a hit, but do not rely on it.

Flame Vent Firewalls

All: Do not touch the rotating Flame Vent firewalls circling the room; contact is fatal. They go from one to two walls mid-fight, then four at 25% and under, splitting the room into quarters.

Flame Vent Tank Positioning

Tank: Hold the center of the room during the four-wall phase. It is the shortest path to rotate away from the fire while holding aggro.

Rocks and Adds

Dps: Always prioritize the adds that come out of ground-slam rocks over the boss. There is no DPS check on Zaudrus himself, but ignored adds (a mix of scamp, watcher, and daedroth types) will overwhelm you. Take the ghost Khajiit's synergy to glow and destroy rocks in one hit with a light or heavy attack; this frees a friendly Flame Atronach instead of spawning an enemy.

Ash Vent

All: Avoid the moving flame laser (Ash Vent) sweeping through the room.

Quake (Hard Mode)

Tank: Step out of Quake's ground eruption and lava pool as soon as you can. It deals damage over time and snares heavily; do not let it slow you near the fire walls.

Ash Vent, Four (Hard Mode)

All: At about 35% boss health, four Ash Vents move through the room at once instead of one. Track all of them, not just the one you last saw.

Rocks and Adds (denser) (Hard Mode)

Dps: Each rock phase spawns five or six rocks instead of two or three: more hostile adds if ignored, but also more free Flame Atronach helpers if you keep taking the synergy and destroying rocks with it active.