This is a simple exercise for good players. When the battle starts run around all of the science equipment to get behind the Tyrant (do not head over to the door which leads out of this room). Once done, wait for him to move over to you and attempt an attack. As soon as you see him preparing to attack, run forward to avoid him and then run behind him. From
here, your only enemy will be the camera-angles. Run around him in circles, whilst slashing him!

Be sure to take full advantage of the periods of time where he actually stops moving altogether (but only stab him once at a time)...