grand architect's temple tutorial?

monster lvl 75
i just don't know what to do
after i deal like 25% of the boss' hp i can't do any dmg to him once the 4 "totems" are activated
but he can kill me in like 1-2 secs ( 4.4k hp 1.5k mana MoM) and a lot of shit happening so it feels impossible to dodge everything he's throwing at you... oh and there's also darkess