Yahar'gul, Unseen Village
More Blood Echoes gained from visceral attacks.
This Rune is found just a little ways past the Yahar'gul, Unseen Village lantern. Head down the stairs and take a left. The staircase here is guarded by a large number of enemies. Fight your way through to a little jail cell area, then proceed outside. Head down the stairs and through the busted wall into a second jail area. Follow the room as it moves around the perimeter to find this Rune up against the cell bars.
Clawmark & Moon
Strengthens visceral attacks. Acquire more Blood Echoes.
Both of these Runes are inside the Yahar'gul Chapel. After reaching the main floor, you'll be attacked by a trio of hunters. One drops the Clawmark Rune, and the other can be picked off the corpse in the middle of the room.
Increases Arcane defence.
When you exit the jail below Yahar'gul Chapel to street level, turn right from the large wagon. Near some blood-spewing enemies and a pyre, you'll find this on a corpse.