The Jet Balloon (ジェットバルーン Jetto Barūn ) is an Emblem Heartless that is found in Kingdom Hearts Final Mix. A Jet Balloon is a green variant of the Aquatank Heartless. They form a symbiotic relationship with Missile Divers, firing them to keep Sora away. Jet Balloons are found only in Neverland on the deck of Captain Hook's ship. To avoid it, fly out of the way or defend against it with Aeroga.
Jet Balloons mirror the appearance of Aquatanks, with some slight color changes. While the Aquatank boasts bright turquoise and blue colors, the jagged sections of the Jet Balloon's round, bloated body are dark, murky shades of sea-green and white, appearing stained in places.
The Jet Balloon's name is a reference to jet aircraft and engines, highlighting their speed and their ability to quickly fire their Missile Diver companions at foes. The Heartless's name is also a reference to a balloon, highlighting their round shape and their ability to float above the battlefield.
Jet Balloons fly away from Sora and launch Missile Divers when he begins to approach. They are also quick to vanish from the area, meaning they must be defeated quickly. A good way to do so would be to approach from below with Aeroga activated, as this helps defend against Missile Divers.