"The mad god", god of knowledge

The mad god was once known by a different name, which has seemingly been lost. But the name is not the only thing this god has lost. His mind too is demented and manic. This god is unpredictable, and over the range of the last few thousand years has earned himself a reputation for meddling in mortal affairs by projecting himself into the overworld. unlike the other gods, he does not do this to help or undermine those of the overworld. He simply does it because he thinks its fun.
There is some speculation that the mad god, just like Zerna, was a god that had once been a mere viro, but had killed a god to take its power. In the case of the mad god, the unknown viro must not have been mentally prepared for what power this would bring.