I would make it 2 hits to kill but swings faster than the sledgehammer/pickaxe with a bit less range
No special stats or gimmicks, just a better melee weapon than the current ones at the cost of utility
Either make it an alternative to the sledgehammer/pickaxe in the same slot, or make it a secondary weapon because it has no utility unlike all other gadgets
(Maybe make it cause bleeding guaranteed on every hit, but that might feel too gimmicky so idk)