Find a FC that has players who can help. Final boss in Arum vail is a joke with players who understand the fight.. Fight boss eat mushroom @ 3 stacks aoe adds when he spawns them. Eat mushroom if you get breathed on. and repeat.

Garuda is an interesting fight . Most the time its on the healers and tanks to keep everyone going. tanks gotta learn the right places to move the boss and pick up adds. Healers need to watch there aggro while keeping everyone alive. Only thing that will help you is to not join DF and get a FC.