this is inaccurate, Anakin didn't scream "I have the high ground," Obi Wan did, because right before it he says "It's over Anakin". You might have to go back and rewatch episode 3.
Obi Wan and Anakin stare at each other, duel a bit and obi wan does a backflip off the droid onto the rock.
Obi Wan: It's over Anakin! I have the high ground
Anakin: You underestimate my power!
Obi Wan: Don't try it.
Anakin: *jumps and gets sliced and diced by obi wan*
This is technically incorrect, it was the will of the children that kept afton alive. The springlock suit would have killed him, had it not been for that fact. The children's drive for revenge is what kept him alive to suffer.