Barb, the last Berzerker. Book 2, Barb and the ghost blade

"Barb is a Berzerker, part of an elite crew of warriors who protect the land of Bailiwick from the scourge of monsters. The evil Witch Head has captured all the adult Berzerkers and Barb's the only one who can save them and free Bailiwick from the scourge of Witch Head. But she's not alone-Barb's got her own amateur crew of would-be zerks, made up of farmers, monsters, and her best pal Porkchop the yeti. This ragtag gang must infiltrate Maug Horn...