Nate the Snake

Nate is a viper which has somehow attained the power of speech. He could be found among the ruins of Magincia in Ultima IV.

Description
Nate would tell the Stranger that it was his duty to bring death to all that lived in ruined Magincia. Should the hero have learned from the bereft Splot that the serpent knew of the rune of Humility and the black stone, the venomous Nate could be asked of such things, and he would truthfully answer that to learn of the stone, the hero ought seek information from the tavern in Britain, whereas to learn of the rune, Barren of Paws must be asked. Regardless of what the snake told the hero, however, he would strike once the conversation was over, attempting to fulfill his geas and kill the still living Stranger.

Trivia

 * Nate the Snake is actually the topic of an exceptionally long shaggy dog story, which features nearly thirteen pages of narrative regarding a dying man who meets Nate, a magical serpent who watches over the remnants of Eden, before the story eventually terminates in a punchline.
 * In the Nintendo remake of Ultima IV (where most character names were omitted and dialogue was significantly modified), Nate can be identified with the demon in the same location. Instead of physically attacking the Stranger, he does a verbal attack, questioning the hero's motivation. He says nothing about the Rune or the Stone.