Lord Valthalak

Return to The Beast's room
For an optional Lord Valthalak summon, return to The Beast's cleared room after the main route. Set spread positions before summoning and keep the tank apart from the ranged group. Assign damage dealers to break away from Valthalak immediately when a summoned enemy begins Defile.
Lord Valthalak
Boss HumanoidValthalak is an optional summon in The Beast's room that demands spread positions for Shadow Wrath and immediate damage on any enemy channeling Defile.
Abilities

Shadow Wrath
Spread the ranged group and keep the tank isolated so Shadow Wrath cannot chain through players standing together.

Defile
A summoned enemy channels Defile on a player. Kill its caster to release the stunned player; healing alone does not prevent the lethal completion.

Shadow Bolt Volley
Hurls missiles of dark magic, inflicting Shadow damage to nearby enemies.
Use remaining damage and healing cooldowns when repeated Shadow Bolt Volleys begin, without collapsing the spread needed for Shadow Wrath.
Tank- Keep Valthalak apart from the ranged spread so Shadow Wrath cannot jump from you into a cluster. Maintain that separation when damage dealers move to a Defile caster.
Healer- Keep your own spread position during Shadow Wrath, call out a player trapped by Defile, and save group recovery for repeated Shadow Bolt Volleys. Defile requires the caster to die, not a larger heal on its victim.
Damage- Switch immediately from Valthalak to an enemy channeling Defile, then return to your spread position. Commit remaining cooldowns during the repeated Shadow Bolt Volleys.