There is a yellow line in front of him. Everybody needs to cross it at the start, otherwise he use his ranged attack that kills in one or 2 shots. interrupt smash and melee step away from him on burst.
This. When we first started doing this fight last week, we had the tank just 180 the boss while me (Assassin) would stay behind. Kept getting killed by chain laser hits. Decided to turn the boss so he faced to the side and had the rest of the group on the opposite side. Keep the healers/ranged towards the back under the panel since there seems to be a melee pulsing aoe.
Our groups in guild usually ignore the Droids.