From the Super Mario Wiki
Beezos, also known as Shy Aways in Super Mario RPG: Legend of the Seven Stars, are a sub-species of Shy Guys that first appeared in Super Mario Bros. 2. This sub-species appears to use tridents as weapons. Beezos also have insect like wings on their back, which allow them to fly.
Super Mario Bros. 2
Beezos first appeared in Super Mario Bros. 2, allied with Wart and the mysterious 8 bits. They are present in three different colors: red, green, and gray. They attack by charging towards the player, in flight, while wielding tridents as weapons. The reds will dive at Mario while the grays and greens follow set horizontal paths. Level 1-2 is the first appearance of Beezos. They fly towards the player riding a magic carpet stolen from a Pidgit.
Beezos normally appear in large groups and seemingly have an infinite number due to not disappearing until the player leaves the portion of the level they appear in.
There are two ways to defeat a Beezo. The players could throw Vegetables or other objects at one, or jump on them, picking it up, and throwing it.
Beezos reappeared in Super Mario Bros. 2's remakes, Super Mario All-Stars and Super Mario Advance, in which they act the same, with the only difference being that they were recolored. The reds became yellow while the grays and greens became red. In Super Mario Advance, if the player defeats a single Beezo, the player would acquire 4000 points total.
The Super Mario Bros. Super Show!
Beezos make several appearances in The Super Mario Bros Super Show!, usually serving as guards, and attacking in large swarms. In the episode "Love 'Em and Leave 'Em", instead of working for King Koopa as usual, they work for Queen Rotunda. Near the beginning of the episode, they attack Mario and his friends, only to be defeated by vegetables. In the episode "The Fire of Hercufleas", the Beezos steal "The Great Balls of Fire from Hercufleas. When the Mario Brothers, Toad, Princess Toadstool, and Hercufleas go to get the "Great Balls of Fire" back, the Beezos get stuck in a bowl of melted marshmallows.
Super Mario RPG: Legend of the Seven Stars
Beezos appeared in Super Mario RPG: Legend of the Seven Stars under the name "Shy Away". They could be found at Land's End and Bean Valley. Although Shy Aways command impressive magical abilities, most choose to run away from intruders instead of fighting them in this game. Additionally, Shy Aways now show a love of watering plants, especially the kind that will attack others for them.
One specific Shy Away works for Valentina during her reign in Nimbus Land. This Shy Away is tasked with blocking the entrance to Nimbus Land, preventing any interference to Valentina's plan. This Shy Away grew a Smilax to block the pipe leading to Nimbus Land. After Mario defeats this first Smilax, Shy Away reappears and grows two more. Eventually, Shy Away creates the Megasmilax, a gigantic Piranha Plant with magical abilities. Ultimately, Mario prevailes over the plant monster, thus causing Shy Away to run away (and accidentally drop the important Seed item).
Shy Away retreats to Nimbus Land. Once there, he is ordered by Valentina to provide nutrients to Birdo. Mario meets up with Shy Away again, and the flying gardener tries to flee a second time. However, the door leading out of hers room is locked, preventing Shy Away's escape. In fact, Birdo holds the key to the door. Thus Mario has to "play" with her (i.e. battle her) to receive the key and open the door.
Once Mario opens the door, Shy Away flies to the throne room, warning Valentina and Dodo of Mario's arrival. After warning her, Shy Away flees for a third time (and is followed by Valentina and Dodo, who also do not wish to fight).
After Valentina and Dodo are defeated, Shy Away attempts to escape Nimbus Land for good (through an invisible path off the clouds), but Mario catches him, and he gives Mario the Fertilizer item. The Fertilizer and Seed can be used together in the greenhouse in Rose Town for a beanstalk leading to the Lazy Shell weapon and the Lazy Shell armor.
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