Dnd aint got barely any lore on this eldritch monster so I fill in a few spaces:
- Elder Evil
- Craves sight of the surface (for knowledge of how to ruin the surface in the most fun way possible)
- Found in purple braziers in aboleth cities (underdark)
- Hypnosis/seduction of people
- Loves creating false order and then suddenly throw into chaos
- Wants people to commit sin/evil stuff etc.
- Older than many other elder evils, possibly parent of some (would even like to see evil things like them in chaos too)

Basically, he charismatic and alluring but leaves yall on fire, insane, and in a pool of like 100 peoples blood when he done with you.
He also a fancy pants.
In Vex's case, he enjoy pulling down her pants in town square and watching her flounder and fluster around while he sippin fine eldritch wine and void cheese. Also random purple fireballs.

Yall can use this in your campaigns and change it around as you see fit, it just annoying that his only cannon lore is "He like destruction, he purple, aboleths like him"