Yodrin:
I have not used this item before, and I wonder how the one use effect is.
Is the one use ability instead of the normal attack or in addition that round, getting 3 att+btb wound in one round?
Does the auto wound count as killing blow, or wound with no armor save?
deadlydeceiver:
Hey,
in short:
RAW the btb wounds are dealt in addition to your normal attacks. (and I think that’s alright when looking at the price tag)
The auto wounds DO NOT trigger killing blow. You need to roll a 6 to trigger it and an “auto wound” skips the roll completely. (Just like a poison 6 won’t trigger a KB )
IMHO there’s only one true question concerning the mace:
Can the auto wounds be used anytime (RAW there’re no restrictions) or just in the CC-phase (in initative)? 
DD