Bubble
Bubbles can be produced by using the B. wand or the B. B. wand. Bubble fish and the seahorse also produce bubbles.
Bubbles travel upwards until they hit an obstacle, but they sink if the player is standing on them. A fan or a geyser will lift a bubble, even if the player is standing on it. Bubbles can across room boundaries.
Bubbles burst when hitting surfaces, vines, stalactites, and stalagmites, but don't burst and pass through without issue through metal spikes and through water. Bubbles can be stepped on by the player and will burst when jumped off them, unless the jump is made during coyote time. Hummingbirds will aggressively burst bubbles.
The bubbles created by animals are light blue in color, while bubbles created by the B. wand are white. If the player pops a 1000 bubbles, they obtain the "BUBBLE ECSTASY" achievement.[1]