Here's how my team runs it (for normal mode). The roles are:
- Runner, who runs the platforms, steals the aura, and kills the vessel with a sword usually. This person then runs to the middle, where everyone meets and staggers Oryx. They stay shooting while the others detonate bombs. Everyone runs back to the runner for protection when bombs detonate.
- One person up on the Deathsinger pillars. This person's job is to weaken all 4 ogres, with extra attention paid to the 4th one. Touch of Malice is ideal for it (I've found) but any scout rifle will do. Have a sniper equipped as backup in case you need to hit an ogre harder or to help damage the 4th one.
- Three people on pillars. You can either assign a person to each one or come up with a rotation system (depends on your fireteam's preferences). They jump up just like in Deathsingers to allow the runner to run platforms. They kill the ogres on their side of the arena, making sure to kill them away from the middle. The bombs appear where the ogres die, so killing them away from the middle ensures no one accidentally detonates them too early, wiping the team or wasting a damage phase. When they're down and the Runner calls them to the middle to stagger Oryx, they run to the middle and do so. Once he is staggered, they go back to their designated pillar and detonate the bomb from the ogre that spawned next to their pillar. They run back to middle for shelter from the explosion.
- A Floater. We have this person up top on the Deathsinger pillars, as well. They help damage the ogres. The Floater is the person whose regular pillar is the one the spark is over in a particular cycle, because you don't need someone to jump on the last pillar. The Floater will also fill in for anyone who dies and needs their pillar covered until they can be revived.
After you damage Oryx, he will either launch fireballs at you or he will pull you into a darkness bubble to fight the Shade (basically an echo of Oryx that behaves like the real thing in Regicide).
If it's fireballs:
- Runner runs at either the front, back, or middle of the arena.
- Pillar people run around their three pillars.
- Floater goes to the fourth, unoccupied pillar (the one that had the spark over it in the preceding damage phase)
- Ogre shooter runs back and forth on the Deathsinger pillars
If it's the Shade:
- Oryx will pull players in 1 by 1.
- Players on the outside will kill enemies to prevent them from entering the darkness bubble. This allows the person(s) inside to focus on the Shade and not have to worry about Thrall taking down their health, which doesn't replenish once inside the bubble. A Blessing Ward of Dawn is incredibly useful for this part.
- Players inside kill the Shade as quickly as possible, because after a certain amount of time everyone wipes.
Rinse and repeat until Oryx is dead. Hope something in all that will be helpful!