1st boss: Annihilation Droid XRR-3. Your group will either split up or group together, if you split up you mostly need to worry about your group, but you can change position to reach everyone when needed. The tank will take pretty high damage and needs to be healed. There are 2 abilities you need to worry about, one spawns a circle on the ground, get out of it. The second is the boss missiles that needs to be avoided by hiding behind the turrents. If your DPS hide as well, this should be easy to heal, however, if or when the DPS needs to step out and continue to hit the boss, you need to position yourself so that you are out of LoS for the boss, but still have LoS for the DPS, this will also mean healing will be much more intensive.