Ybarra

Old Ybarra is one of the Ten Pirates of Hawkins, and has one piece of the Treasure Map of Hawkins, which is needed in Ultima VI.

After killing Hawkins, Ybarra went into the dungeon Shame to find treasure. He didn't find anything but hunger, the way back blocked by beasts. The Avatar found him down there, and exchanged food for the piece of the map (Ybarra had already eaten his belt!). But Ybarra was already too weak, and died only seconds after giving the map piece to the Avatar.

Easter Egg
This is in reference to one of the game's developers and founders of Electronic Arts, Joe Ybarra.