They usually come in groups of 3 to 5, and attack in flocks, usually in a formation such as a zigzag, "V", or a vertical line. Some Bronto Burts will chase after Kirby trying to run into him, some just take off and fly away very fast when Kirby gets near, out of fear. Some stand on ground and then attack or fly straight ahead when Kirby comes too close. Just like Waddle Dee is the most common enemy on the ground, Bronto Burt is the most common enemy in the air. Also like Waddle Dee, most of Bronto Burt's behavior remains the same throughout the series. One could guess that they are the "Waddle Dee" of the sky.
In Super Smash Flash 2
Bronto Burt will appear in a yet unnamed Kirbystage, in the Adventure mode. Bronto Burt often flies and strikes characters that are in midair. The only time they cannot strike is when either a character is underground, shielding or air-dodging. This enemy is easier to hit while using an aerial attack or an up special move.
It also appears in Dream Land on Beta version, as a background character. They come in a group of 3, in a diagonal line and will not affect the battle in any mode directly.
The Bronto Burt and the Waddle Dee in Untitled Kirby Stage