Pew the Rat

Pew is one of the two main antagonists (the other is Long John Silver) of the animated series, The Legends of Treasure Island, which is loosely based on the 1883 book Treasure Island by the late Robert Louis Stevenson. He was based on the character of the same name from the book.

He was voiced by Rob Rackstraw (uncredited).

Personality
In the original book, Pew was simply a blind former pirate who hands Billy Bones the Black Spot and ends up trampled to death by horses before the journey even begins. In the series, he's turned into a sinister villain with magical powers. Pew is blind, but don’t underestimate him: he still has perfect hearing and sense of smell. (Perhaps, Pew uses mind's eye, like Uonuma Usui from Rurouni Kenshin series,  which is actually supernatural hearing that lets him hear another's heartbeat, muscle contractions and bone friction thus enabling him to read their emotions and physical position). Pew's spells terrify the protagonists and allies: even Long John Silver is afraid of him and tried to get rid of his terrible boss. Pew was shown to be without pity and mercy and in the end he actually killed one of the protagonists.

Appearance
Based on Blind Pew from the original novel, he is an anthropomorphic blue giant rat with glowing gold eyes that he can't see with. In both seasons, he wore a red robe-looking outfit with the hood on his head, covering his (as the episode Double Cross shows) pointy wolf-like ears. In the beginning, he appeared to be a simple pirate with the desire of finding Flint's treasure but as the story went on he was showed to be more like of an evil sorcerer, conjuring evil spells and creating monsters to fight the protagonist.

Also, in the end, his true nature and goals became even more and more obscure: he revealed to have no interest for jewel or gold of the treasure (he actually defined them "mortal baubles") and his real interest was a particular artifact present in the treasure.

Once he was able to grab the artifact he seemed to become invulnerable to anything; in the end, he was apparently defeated but even his disappearance was obscure: his body vanished in a cloud of green smoke while his clothes remained intact. So, in the end, you were actually wondering if he was really gone.