Kumanda slays-nine-men

[Hand_of_Vecna]

Minor character from Way of the Wicked book 2. His greatsword is listed as doing 4d6 damage, but nothing in his statblockseems to justify this. Is it a typo? Is there a common ability a lvl 5 pathfinder Barbarian could have to allow this? The sword itself is a mwk greatsword and it's a medium creature.

[Extra Anchovies]

Well...
https://c2.staticflickr.com/6/5139/5415327750_a6f6e629f5_z.jpg

[Snowbluff]

The answer given above is a pretty crummy archetype.

Vital Strike wouldn't work, either...