Gunyolk was a large mechanical monstrosity created by the Factory Chief, one of the most important members of the Smithy Gang, and appeared in Super Mario RPG: Legend of the Seven Stars. The mechanical creature was used as a weapon in an attempt by the Factory Chief to destroy Mario and his allies. In fact, Gunyolk and the Factory Chief were the only things that were standing between Mario's group and the leader of the Smithy Gang himself, Smithy. Engaging the group in combat Gunyolk proved to be a worthy adversary, knowing a large abundance of attacks and capable of using the powerful Breaker Beam attack. After a long battle Mario and company managed to beat the large machine monster and its master.
A beta enemy palette swap of Gunyolk exists that is unused in the game. It uses the magic attacks: Lightning Orb, Mega Drain and Spore Chimes.