Here is what I gathered from my fight with Ultima's Bane.

Abilities used by Ultima in all phases:

I phase one, and subsequently throughout the fight, Ultima will put Viscous Aetheroplasm on hit primary target. It is a stacking debuff that causes each use of Viscous Aetheroplasm to deal more damage (A la Burrs in Aurum Vale). Due to this, you will be forced to do a tank swap at every three stacks, maximum of four stacks. 5 stacks will cause the next Viscous Aetheroplasm to hit for so much damage, it will be a one shot.

Ultima has a general AoE called Ceruleum Vents. It deals 400 to 600 damage, and goes off periodically with no warning.

His last ability is Homing Lasers, which will target one member of the raid and deal damage to them. As well, anyone within 5 yalms of that targeted person will take damage. This damage is not split between players.