Defend The Doctor Achievement
Defend The Doctor10
Ensure Dr. Pessich survives until end of Castle.During the mid way point (sort of) after walking across a short outside balcony you'll enter a big cave and see this doctor on a computer, get your team mate to defend him. Now there will be 4 doors that open one after each other so get your grenade's and grenade launcher attachment ready and take the enemies out as quick as possible so you don't suddenly become surrounded. After this the doctor will follow you and stay around corners until you've killed all the enemies in that section, it should be pretty straight forward from now on to keep him alive.