Shogghorath

Shogghorath, The Storm of Retribution, The Fallen Father, an ancient Yagathian demon and rival of Ayathogoth when he became the creator of the horrible beings known as the Fallen Gods.

The arrogance of Shogghorath led to his downfall and twisted gratification from the pain and suffering eventually caused him to gain power over the Universe.

Mythology
His evil and loathsome ways were known across the Universe corrupting the minds of everyone in his wake and making murder and chaos common among the mortals.

"'Shogghorath, Master of Retribution knows no bounds of vindication against the Universe...He is forever loathed in his domain waiting for the next soul to torment...Across the Realms of existence and beyond he travels stifling the life out of evildoers...Alas, the awakening of the frightening master with many blood-soaked arms strangling his sacrifice...'"

Shogghorath was going to fight against Ayathogoth to destroy the Outer Dimensions claiming himself as ruler over the Universe

Then Ayathogoth was tempted to destroy Shogghorath only ended up sparing him because that was against his nature and morals.

The Creation of the Fallen Gods
Shogghorath eventually created his children of evil intentions called the Fallen Gods to overthrow Ayathogoth and claim the Universe as their own.

He wanted to turn the Outer Dimensions into a place of suffering and damnation by destroying the very foundation and then rebuilding it into a realm for the Fallen Gods.

After he weakened and defeated Ayathogoth his Fallen Gods claimed a portion of the Universe as their domain to rule over the balance between purity and The forces of darkness.

This came to an end when the Astral Masters were born from the remains of Ayathogoth and defeated the children of Shogghorath.