Ward cliff coil and glacier quakes smack. For the servitor boss you want as much spread out dps as possible I saw people doing heavy wave frame gls on contest. We just used two glacier quakes. I just read the final boss part, that one is kinda tricky, gotta stay on the move. If you have a wellock there is a barrel on the front right of the arena you can chill on to avoid the direct lightning damage and grand overtures works pretty well. Thunder crashes with cuirass right at the start and then gls also work pretty well. I messed around on my hunter and ran sleeper and it did some decent dps provided you can hit crits.