27. During your battle with Victor, you will follow a corridor and eventually come to a doorway that you need to slash through. Once you do, The First relic will be just inside this room, down the small set of stairs and to the right.
Heart of Darkness
29. When you leave the Asylum by choosing the right option, you will enter the next area along a broken stone path. Take a few steps forward and then make a right down the walkway through to find the Prism of the Brothers relic.
28. Follow the path up and around, killing the enemies that appear, and you will eventually come to a dead end that you need to destroy to continue. Before you do, go to the right to find the Ashes of the Unnamed relic just sitting there and get your Relic Hunter achievement/trophy.