i made a post similar to this but this is my theory mainly on how the supreme is literally the universe in itself

  
1. in paris special when emonette tried summoning gimmi, the voice says “reality IS the supreme”

2. you would think that someone as powerful as the supreme would be able to easily go and catch betterfly himself if he can rule a whole universe, rather than needing TWO teenagers entrusted with the most powerful miraculouses to do it

3. in stellar force special he talks to moddler about being freed

my theory is supreme used the absolute power to rule the re-verse and his sacrifice was becoming one with the universe. i think before using this power, he could’ve been;

\- a past guardian (possibly fu or suhan or any other guardian)

\- literally anyone (it’s unknown the past of the reverse, the miraculous could’ve been stolen, or easily obtainable)

\- a member of that counci, maybe they succeeded in this universe and the endgame plan was for supreme to rule the universe or he just got greedy and betrayed the other council members and used the miraculous for himself

i also believe his end goal could possibly be to rule the multiverse which is why he makes an appearance in stellar force (or he just wants to get revenge on ladybug and chat noirs universe for turning two of his villains against him)

also in stellar force he has no bodily form, since he isn’t human (in my theory.)

i also believe that blue lightning in recreation was supreme contacting cerise. the scene (i believe) was the day of recreation which was around the time stellar force takes place where the supreme made an appearance in the universe. (stellar force takes place between london special and start of s6 and london special takes place the night of recreation)

i don’t know why exactly hed contact her but he definently was involved in the quantic universe around that time so who knows

theory: the supreme IS one with the re-verse