In the battle with Dr. Krone's gigantic Sentinel, when you destroy one of his 
guns with the Pulse Gun, Krone will send artillery raining on your roof. In 
order to escape this barrage, slow time, and go into the far right corner. Face 
the wall and look up at Krone's Sentinel. Jump up on the platform. Keep running 
to the right into the corner. You will take no damage while in that corner. This 
works for all three barrages.