My 5e group is going through a conversion of the ancient tech crashed spaceship in a fantasy world adventure path of Iron Gods. While in the Mad Max wastelands section the party has just defeated an orc warlord with an unholy magic chainsaw. The party hexblade is willing to give up his greataxe and a hand to attune to it just so he can say groovy a lot. I see the DMG does not have chainsaw stats in the modern sci-fi section, just a reference to an intelligence check to figuring out how to use them. Any good stats for an unholy chainsaw appropriate for a 6th level party?