- Observe the boss' attack pattern so you know when you'll need to heal.
- Rather than spending time Stoneskinning everyone, I'd suggest helping to kill the orbs to be safe.
- Your party members can make life difficult if they try to ignore mechanics, so watch their behavior.
- Note the arrangement of knights as they spawn in the last phase. Either bait the ground AoEs out of your immediate safe path or move vertically and then horizontally to reposition in the new safe zones.
- Reserve your instant cast heals in the last phase in case people screw up.