Closely related to the bombat of Sessymir, the baybat's spherical body produces light instead of oxygen.  The greater the build up of gases within the creature's body, the more luminous it becomes.  The baybat can be found in Sessymir, Arnkaksak and the Oshalla Ocean where its pretty light has tricked mariners for centuries.  The baybat will rise as its gaseous state increase and can shine so bright as to be confused with stars.

In Arnasak, the creatures are used to light homes.  The Sessmirians' prefer to use Cold to light their way.