Balloon

Balloons are entities that float upward when placed.

Usage
When on a mob or a fence, balloons attach to the mob or block, similar to a lead. Balloons float into the air faster than the speed the player flies up, but remain grounded if tied to a fence. If tied to a mob, the balloon floats away and carries the mob high into the air, before both eventually despawn.

When a balloon is shot by an arrow or a trident, or floats into a solid block, it pops, summons particles, and is destroyed. It drops nothing. A balloon tied to a fence post does not burst when a player strikes it in any direction; instead, it gives way and returns to its usual position.

Trivia

 * In real life, helium gas is used to make ballons float up into the air. This is because helium is less dense than air.

History
Ballon 風船 풍선 Воздушный шар 气球