Go away, scat, skittle, skibobble! The horn is mine! Mine I tell you!
Gutsco appears in the Subterranean Lake and has stolen one of the dwarves' Horns of Ice. After he is defeated once, he follows the party as a shadow to the Dwarven Hollows until they near both Horns, where he promptly steals both of them.
The party pursues Gutsco with encouragement from the dwarves, but Gutsco escapes. He runs to the Molten Cave, where he heads to obtain the power of the Fire Crystal now that he is protected from the cave's hostile magma thanks to the Horns of Ice. The Warriors of the Light find him at the crystal room in the depths of the cave, and fight him in his state of empowerment granted by the Fire Crystal where he takes the form of the Salamander.
Gutsco is fought twice as a boss: once as himself at the Subterranean Lake, and later as Salamander at the Molten Cave.
An errand mentions Gutsco.
Guzco is the leader of the rogue Clan Borzoi, and like in Final Fantasy III, he is fought twice: once in his human form, and later as a fiend.
Gutsco appears in Final Fantasy Trading Card Game with a fire-elemental card.