Once the dark cloud envelopes the icy battlefield upon which you must face Peach 
Wilkins, save the game, and locate the hostile turret at the end of the room 
when the cloud clears. Load the game, and run to it before the cloud clears, so 
that you can quickly freeze or shock it. Then, hack it so it shoots your 
enemies. Crouch down by the area to your right when facing the turret. There are 
a few barriers here to protect you from enemy fire. However, to avoid damage by 
Wilkins' grenades, keep Telekinesis as your active Plasmid. He will avoid the 
turret's fire, but as long as you stay behind the barriers by the turret he will 
stay at a safe distance. This gives you time to calmly return his grenades using 
Telekinesis until he dies. The turret will take out most of the Splicers. This 
method makes things much easier because it eliminates the hectic "run around and 
hit enemies with the wrench" strategy that is otherwise your only option. If the 
turret is not used as an ally, it can easily become a problem, along with the 
bots triggered by the security camera. By hiding near the allied turret however, 
you also hide from the camera's view.