first of all, i snipe at those templar then only engage petrova and RUN don't the slope. the slope have stuff situated strategically to keep my armor and life high enough to survive those black hand shooting from behind. once i reach the bottom, petrova is 1 floor right above and i finished her with volt gun. easy, she got stun and stand still for me to shoot to death. those black hand upstair are no more threat because i let those visceroid inthe cell stay alive managed to kill almost all of black hand leaving 2 for me to finish them off.