Air is a feature in Mope.io, similar to "oxygen" in other IOgames. If you dive or dig, your air will slowly decrease. Certain animals can hold the air much longer than other animals such as the Crocodile. When the air bar reaches 1/4 like all other bars it will make a red flash saying: LOW Air. You can regain air by going into whirlpools or hiding holes. If not regained the animal will automatically stop diving or digging.