hello, most of the damage is earth, so earth set with magic lvl for mages, a sleep shawl for a rps should be enough and a gil neck for eks with some earth protection
get the eks to the middle of the room blocking the monsters and shooters in one side, with lower lvls/mages behind use ava to hit the minions, when the boss spawn hit it with sds, you will need to follow the way to other rooms to keep killing the boss but mechanics are pretty much the same in all rooms, stack the group in a side and eks stay pretty much in the center away from the rest of the team
gaspar a br streamer made a really good video explaining about tatics i will leave the link V :
https://www.youtube.com/watch?v=GWhZrsJfFrQ