In Curse Of Strahd, the Heralds of Dawn invaded the Vallaki Vistani Camp, and Zandros took Peanut Butter alongside other horses as he escaped with other Vistani. She was rode by Floriana until they reached Jeny's Stuttering Shack, where the adventurers defeated the Vistani in combat. They took herself and one other Vistani horse, Jay, intending to sell them to the Arasek Stockyard.
Peanut Butter was also employed to be part of a strange type of watercraft: Tobias Villie Broadnose Cogsmith cast a Spell to allow her to walk on water, propelling a boat across Lake Zarovich alongside her fellow horses Pony Danza, Whinny Houston, Sarah Jessica Parker, and Verity. The group decided not to sell her in the end, and ended up taking her to raise a population of horses at Argynvostholt by convincing her to mate with Jay.
She served as one of the fastest horse in the community until the Slaying Of Strahd.