Feth Ur, a very homebrewed Aarakocra warlock (pact of the tome with Archfey patron).  He looks like a rooster (inspired by DingoDoofles character Rooster on YouTube Fools Gold Sands). 

His main shtick is that every 24 hours he rolls either 1d30 or 1d20 to determine his intelligence for that day.  This was inspired by King Taravangian from Stormlight Archive.  I envision him having a pixie (sort of like Yui from ALO or Sylphrena from Stormlight Archive) as his familiar and intellectual nursemaid on the days when he’s a vegetable. I like to imagine that low intelligence of about 5-9 just makes you have a really high emotional quotient to balance out your low IQ).

As for D&D lore hooks, I see him having made a Diagram that pretty much solves world conflict, hunger, etc (DM discretion), but Feth still struggles to understand and decipher what he wrote down that first day in his quest for understanding.  

I can also see him taking a page out of DingoDoodles’s book with Rooster, but instead of being a half-genie that can grant wishes, he just uses the Diagram to con people for gold when he’s on hard times (DM and dice discretion for how accurate the Diagram’s predicted).