Met Ulthane today. Killed a bunch of pigeons...er, I mean Angels. My score would have been astronomical if the game kept it after each time you died :/
Quite a few tries later I finally made it through. Squashed Uriel and went after Griever. The drowned subway station motif was neat. The more levels I play, the more I can see how this can be compared to Zelda. Griever is the easiest boss so far. A total wuss compared to Tiamat.