It involves Banjo crouching down while Kazooie shoots a Blue Egg forward. Eggs fall due to gravity and bounce unusually but predictably.
By holding down the button, the pair transfer into the Breegull Blaster (タマゴばきゅーん, Egg Kaboom), where Banjo can move while Kazooie can rapid-fire further eggs. While using the Breegull Blaster, eggs don't travel as far and deal less damage, but fly perfectly straight. Banjo can turn and use all his jumps while holding Kazooie. Pressing crouch or shield ends the move.
When used by Kirby, he will fire eggs from a Kazooie puppet in place of the real character.
Blue Eggs are introduced in Mumbo's Mountain of Banjo-Kazooie as the duo's sole projectile attack. With Banjo crouching, Kazooie can fire up to three eggs at a time in a straight line forward, or in a bouncy pattern backward. Eggs are often fed into holes or other suspicious objects to solve puzzles, while they deal low damage to enemies. Banjo-Tooie allows Kazooie to fire eggs in any direction across an infinite distance using first-person aiming, including while flying or swimming underwater, and also introduces other sorts of ammo types such as Grenade Eggs. Kazooie can carry up to 100 Blue Eggs at a time, though Cheato can double this limit.
The Breegull Blaster is taught in Banjo-Tooie's Mayahem Temple. Upon entering certain areas, Banjo automatically wields Kazooie like a shotgun, turning the game into a first-person shooter. Kazooie can fire eggs continuously in this mode. The game includes a multiplayer mode where four players can fight in the game's FPS arenas, playing as different characters with their own unique egg-shooting birds.
The move also appears in Banjo-Kazooie: Grunty's Revenge, wherein Banjo can perform it anywhere after learning it from Bozzeye, replacing the normal egg shooting.