Air

Air, previously known as Bubble, (voiced by LeVar Burton) was a lost bubble who appeared in "BMO Lost." Once BMO found themselves lost in a forest, Bubble brought itself up to help BMO back to the Tree Fort. Bubble first met BMO when they tumbled down a hill and cracked their face plate. Bubble then emerged from a cracked mug and said it had been lost in the forest for a long time, and was feeling the need to give up. However, BMO's determination to get home kept up Bubble's mood. After some trials and spending so much time together, Bubble and BMO developed a friendship, making Bubble feel no longer lost and instead more at home with BMO.

At the end of "I Am a Sword," BMO says "I like Air" when Jake suggests they go outside for some fresh air.

During "The More You Moe, The Moe You Know (Part I)," BMO tries to consult with Air about his decision for growing up.