A tribal sword with an alien inner mouth/tongue as a handle, the blade covered in serrated jagged features and sporting ceremonial markings etc...
for increased badassery, the blade can be mechanically reversed at high speed so that it retracts and extends out the opposite end of the handle making for a cool money shot when the sword is held up to the sky, suddenly it retracts down to be used in a downward hammerfist type motion without the predator moving his hand, for executions of it's defeated trophy kill.