Queen Grannicus is a villain who appeared in Loonatics Unleashed, as a future version of Granny - ironically she would be an enemy of Tweety and an ally of Sylth Vester (thus being almost an exact opposite of her ancestor, who was a fearsome defender of all things Tweety).
Queen Grannicous is a royal descendant of Granny, who didn't want The Royal Tweetums (Tweety) to claim the throne and allied with Sylth Vester (Sylvester) to prevent that. To prevent suspicion, she used her scepter to disguise her voice while talking to Sylth Vester. Both were defeated. She is also similar to Darth Sidious and was likely a parody of said character (much as Sylth Vester was a parody of Darth Vader)