Lets look at Amputator's damage-
http://forums.spiralknights.com/en/node/117917
Oh dear, no one will use this. Maybe they will at first because it's new, but not long term because its damage sucks and it's a damage weapon.... So lets talk balance a bit-
1) It would be wrong for it to deal less than say, combuster against neutral enemies, especially slimes
2) It would be wrong for it to deal more than leviathan blade
3) It would be wrong for it to deal less than or more than cold iron vanquisher against non-undead/slimes
I propose balancing them in the following ways: