Location: Lower Crypts (Chapter 1)
Phases: 3
Phase 1: Summoning Sickness
Zarthus will primarily cast 'Shadow Bolt' (single target) and 'Corpse Explosion' (AoE on summoned minions). He will also summon Risen Minions. Focus on eliminating the minions first to prevent being overwhelmed. Dodge the Shadow Bolts and move away from exploding corpses.
Phase 2: Dark Ritual
At 60% HP, Zarthus will begin a 'Dark Ritual', channeling a powerful AoE spell. During this, he is vulnerable. Interrupt his channel if possible with a stun or high burst damage. He will also summon more resilient Greater Skeletons.
Phase 3: Spectral Form
At 30% HP, Zarthus enters his spectral form, gaining increased movement speed and frequently teleporting. He will cast 'Void Zone' (AoE damage over time) and 'Life Drain' (heals him while damaging you). Stay mobile, avoid Void Zones, and use your strongest abilities when he reappears. Healing potions are crucial here.
Weaknesses:
- Holy Damage
- Stuns and Interrupts (especially during Phase 2)
Rewards:
- 500 Gold
- 500 XP
- Necromancer's Staff