Pile o' Balloons is a character-specific object belonging to Wes, placed in his inventory at the beginning of the game. It allows Wes to blow up balloons, at a cost of 5 Sanity each.
Balloons spawn in a variety of colors and shapes, and they can be pushed around. Balloons have a small chance of distracting mobs (who will attack the balloons instead of the player). They will pop if attacked, or if a nearby balloon pops, setting off a chain reaction. Popping a balloon causes 5 damage. Like all Character-Specific Items, this item shows on the map when dropped.