The Temple of Blood is home to a cult based around the Bloodstaff with a long history in Needles. Apparently somewhat benign in the past, they've since gone rogue and have apparently killed the right hand man of the Mushroom Priest in Needles (you can find his body in the Needles/Ammo bunker - show his Ruby ring to the Mushroom Priest to get the story about the Bloodstaff).