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Bē (ベエ) are large flies found in Super Mario Land 2: 6 Golden Coins and Wario Land: Super Mario Land 3. In both of these games, Bē are rather rare and can technically deal no damage, since they run away from Mario as he approaches.
Bē first appear in Super Mario Land 2: 6 Golden Coins, where they can be found in one of the Tree Zone levels and two of the Macro Zone levels. They typically remain in one place when undisturbed, but they quickly fly off in a diagonal manner when approached by Mario. Their runaway flight is just as fast as Mario's top running speed.
Bē reappear in Wario Land: Super Mario Land 3, behaving similarly to their previous incarnation. They are found in the first three stages of the SS Tea Cup. They are also given an animation when idle and fly away in a curved angle. They do not move if Wario crouches, which makes it possible for Wario to jump on them. If Wario manages to jump on one, a 10 Gold Coin appears.