Waluigi is personified as a comic relief character and a boastful, ill-tempered foil to the more humble and gentle Luigi. He has bad chemistry with most other characters besides Wario, and is an openly rude and mean-spirited troublemaker. He has a perpetual scowl and is quick to anger, with earlier bios stating that he dislikes others being happy. In his one outing as a central antagonist in Dance Dance Revolution: Mario Mix, Waluigi claims that his reason for obtaining the Music Keys is to be the best dancer in the world, while bragging about using his power to spread chaos and control "the masses". In Mario Tennis Aces, Waluigi points out that his and Wario's reasons for attaining Lucien was so that they could become the best tennis players in the world. Waluigi's original bio in Mario Tennis also pointed out that he seeked to become as popular and as beloved as the Mario Brothers. His victory celebrations often highlight his self-aggrandizing nature and vanity, and occasionally contain vulgar elements as well, such as in Super Mario Strikers where one of his victory animations involve him performing a pelvic thrust.

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