Mal

Mal, the Empty God, was the second god to emerge independently from chaos. He was responsible for the death of Aål, the Firstborn God.

Worshipers
Worship of the Empty God is understandably not popular. There is a common understanding about Mal's "favour" towards his worshipers; he is known to sporadically respond to prayers offered to him, though often in a highly destructive and undesirable manner for whoever offered the prayer in the first place. Most of Mal's worshipers offer no prayers to him directly as a result, or do so only in a desperate effort to repel his influence.

History
Mal followed Aål out of Chaos, but became dormant for a long period of time while Aål and his offspring created. Eventually, Mal would emerge and slay the Firstborn God, and then seemingly vanish into the Plexus. It was (much) later revealed by the Void Immortal that Mal was actually pushed back into Chaos by the light of Aål's sun.

Entirely unrelated to the other gods, Mal is not known to have sired any offspring deities or to have created any permanent dominions. His influence waxes and wanes in the material plane (and the other planes) seemingly at random.

Genesis
During the events of Genesis, an outpouring of power from the Fluid Nothing occurred when the summoner Lantis inadvertently summoned Titer (whom he thought was just a spirit of some kind) to kill Albrek Bane. This, coupled with the coincidental gathering of the necessary components and the light of Aal from Tahl's lantern, allowed the world's first appearance of the Void Immortal.

Mal may also have spoken with Darr Ude at this time, as his soul was sent to the edge of Chaos after his death.