Belial is the final boss of Act 2. You fight him in a circular "arena" with very limited movement space, and the fight spans over three phases.
Phase 1
During this phase Belial stays out of range on his balcony while summing adds. While this phase is pretty easy, you might have problems if for example you are undergeared or you manage to get trapped by the adds. Remember that ranged classes have it worst in this phase due to the limited movement area.
Phase 2
This phase is when you actually get to fight Belial. During this stage the adds will still spawn but in a limited number. Belial attacks in melee range but can also throw fireballs which you must be careful to avoid.
Phase 3
This is where Belial gets serious! He will reveal his true form and smash the arena. Attacks during this phase do very high damage so you must be careful to avoid them. He was three abilities during this phase:
- Arm Smash Combo - Belial will smash the ground with his giant hands dealing massive damage. This is usually a one-hit kill move, but luckily there is an indicator before he executes it. A green dot will appear on the floor approximately 1 second before he hits. Make sure you move well away from the dot as the smash also does a lot of AOE damage. This is a 3 part move. First he will smash with one hand, then with the other, than with both combined. When executing this move, Belial is open to hits!
- Arm Drill - This is the same as the previous move but he will only do one hit.
- Poison Breath - Belial will use his poison breath in a wide area so make sure you run when you see him about to execute this.
- Poison Explosions - This is the worst attack Belial has in his arsenal. He will stick both his arms into the ground and cause green circles to appear on the ground. These circles explode after just a short duration so make sure you keep moving. The amount of green circles is very high but there is always a way to avoid them.
In Inferno mode, Belial will enrage after 3 minutes greatly increasing the amount of pools spawned in the Poison Explosion attack.