Originally in the Japanese version of Super Mario Bros. 2 Birdo was a male dinosaur cross dressing as a female (hence the bow) though Nintendo decided to take away it's gender in the American version of the game. Birdo used to be a boss character in many levels in Super Mario Bros. 2. The twist is that in this game there was more than one Birdo. The pink Birdos can lay fire eggs, the red Birdo's can shoot the fireballs and eggs out of it's mouth, and the green Birdo only shoots fire at the player.
In the remake of the 2nd Super Mario Bros. game for the Gameboy Advanced called Super Mario Advance has a robotic Birdo as a boss named Robirdo. This is one of the very few games where you can clearly understand what Birdo says.
Birdo appears to be a main character in Wario Woods which is a puzzle game for the NES. Birdo, Wanda, and Toad team up to go against Wario. Birdo is not playable in this game but plays a major part aiding Toad and Wanda.
Birdo yet again appears as a villain in the Square Enix game Super Mario RPG: Legend of The Seven Stars. Since the release of this game this has been the last one where Birdo appears to be a villain as she now has somewhat of a relationship with Yoshi.
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