Sonic Headcanons/AU Stuff, because I'm just in the mood and accidentally made a Sonic AU while rewriting the story of Sonic Forces... As ya do.
The anthropomorphic animals in this universe are called "Faunans", because fauna is a colloquial term for the animal life in a place
Sonic grew up in the Christmas Island orphanage starting at age 3 1/2 due to his dad accidentally drowning at sea during a storm they were both in, which laid the groundwork for Labyrinth to give him full blown traumatic aquaphobia
Mighty and Ray became the first two people to successfully catch up to and keep up with the fastest thing alive, leading to the three becoming a trio of little troublemakers
Adding onto the childhood friend angle, the armadillo and flying squirrel are the only people who can call Sonic "Nicky" until Sonic informs Tails of the nickname after Adventure, though the fox keeps it for when they're alone
an 11yo Sonic first went Super as he was falling to Earth after blowing up the Death Egg in Sonic 2, surprising both himself and the 4yo fox piloting the Tornado
The Super Emeralds and thus, the Hyper State are only possible on and above Angel Island, due to the presence of the Master Emerald
Out of all the small animals in the world, Flickys are the most sensitive to Chaos Energy
Combining the previous two, the first person to go Hyper was Mr. Miles "Tails" Prower, sharing the immense energy with four Flickys who followed him and Sonic into the Death Egg
Mania was erased from everyone's memory in a last ditch effort by Heavy Magician to lay in wait to eventually defeat Sonic forever. Her plan worked until (now 12)Sonic got sent into when he was supposed to be 17 and also dead(?), awakening everyone's memories upon finding one of the Phantom Ruby copies Ivo made. This is also why the Present Sonic of the time was able to act like he hadn't been tortured, due to the sudden rush of "Hey wait... I've seen that thing before!"
The Chaos Emeralds are sentient, beginning to appear to their unofficial protector in his dreams as a Blue Ricky, Magenta Pocky, Red Pecky, Cyan Flicky, Yellow Picky, Green Cucky/Clucky/Cooky/whatever the hell you wanna call the chickens, and a Gray Rocky in between Adventure 1 and 2