Old Blind Pew (also known in-game as “old dog”) is an old, unwashed dog that Guybrush finds in the Blood Island cemetery. He really does seem to be blind since he wears smoked spectacles and has to sniff around to find treats; Guybrush says he’s “not very social.” He sleeps in a coffin doghouse and appears to be Mort the Gravedigger‘s pet.
In order to cure Griswold Goodsoup‘s hangover, Guybrush has to find “hair of the dog that bit ‘ya.” So he offers Old Blind Pew dog treats (in the regular version) or a half-eaten maggoty biscuit (in the Mega-Monkey challenge). Pew chomps down on it and, during the process, bites his arm. Guybrush is also able to easily get some of Old Blind Pew’s shedding dog hair.