Good catch Mamut, I know that blood presence healing doesn't combine with a blood aura but I wasn't sure which would override which if you had multiple blood aura buffs (in which case the auras are superior) but I guess we know now . I actually made my observation on my tank who uses frost presence and didn't check my DPSs (whom are in blood presence). So I guess one would need to set their DPS DKs to unholy/frost presence to benefit from the stacked auras