A few of our guild (lvl 50s) did this on our server and invited a few lower levels around Coruscant, just to help them along with some nice loot. Everything was obviously easy for me as the tank as I was resisting every attack thrown at me, until I suddenly got 1 shotted by an unknown attack. 15k HP suddenly wiped. Seems he has an uninterruptable insta-kill nuke.
He casts a debuff on two people. They need to run away from each other. If they are too close anything near them will get 1-shotted.