Bob-ombast

Bob-ombast is an attack that Admiral Bobbery learned in Paper Mario: The Thousand-Year Door. This attack is one of the most powerful attacks any of the partners are capable of, with a base Attack Power of 8. However, the attack costs 9 FP, the second most costly move of Mario's partners. Bobbery can only use this attack after being leveled up to the Ultra Rank. In order to execute this move, the player must rapidly tap the button to fill the gauge as much as possible. This attack is similar to Bombette's Mega Bomb from Paper Mario. Bobbery can perform a Stylish move by pressing as soon as he lands on the ground after exploding.

This is the only non-jump attack that can deal damage to flying enemies, except for a First Strike Bomb. It will even ground Parabuzzies and Spiky Parabuzzies, even though they take no damage from explosions.