Baby Wario is one of the five baby characters playable in Yoshi's Island DS. He is unique to this game, created specifically for it. He uses a magnet to attach to magnetic blocks and grab coins throughout the game. He is one of the only Mario Babies to not appear in other mario media, such as spin off games like Mario Kart, Mario Party, and the Many Mario Sports games.
He is Wario's younger self before he becomes an rival of Mario in Super Mario Land 2: The Six Golden Coins.
Like his future self, Baby Wario is voiced by Charles Martinet who also voices Mario and his baby self, Charles Martinet also voiced Luigi and his baby self as well.
Yoshi's Island DS
When Baby Wario was originally kidnapped, the Toadies found his crying to be very annoying, so they left him alone in World 3-5. Some time after that, Yoshi, who has been washed away by a large wave and separated from the Stork and other babies, finds him. Baby Wario assisted Yoshi throughout the rest of World 3, but he gets away from him after World 3-8, joining up with a group Bandits in hope of even more riches. Yoshi and the rest of the babies meet up with Baby Wario one last time in Bowser's Castle, having an argument with Baby Bowser. He helps the Yoshis by defeating Bowser on the back of Purple Yoshi. After the castle is destroyed and the team finds the babies, Baby Wario lands on a very large Treasure Chest filled with his treasure. However, Baby Bowser falls and lands in the treasure as well, initiating an argument over it.
At the end of the game, it is revealed that Baby Wario, like Baby Mario, Baby Luigi, Baby Bowser, Baby Donkey Kong, Baby Peach, and Baby Yoshi, is one of the seven star children.
Baby Wario shares many physical qualities with his adult counterpart. They both have a large yellow cap and a big, pink nose. Under his cap, brown hair can be seen. Like Baby Mario and Baby Luigi, Baby Wario wears nothing but a diaper and a hat. Since he is a baby, he has short, stubby hands and feet.
Baby Wario's cry is the loudest out of all the babies in Yoshi's Island DS. Just like his adult counterpart, he has a tendency to be very greedy, hence the magnet ability. When Yoshi and the babies get to World 5, Baby Wario is seen arguing with Baby Bowser. This gives the idea that Baby Wario's greed may lead to him being quite argumentative. Unlike the other babies, he can talk shown by his arguing. During the final boss battle, Baby Wario rides a Purple Yoshi.