Axiom is a super sonic vessel from the 06 era,after the reset it split fleetway out of Sonic surpression along with sonic body intact but heavily damaged after sonic sacrificed himself over shadow and silver leaving them behind to save the timeline,The reset in progress made fleetway adapted to the endless void turning chaos-energy into negative chaos-energy while the vessel became its own thing as it wasn't with them,after fleetway got out of the void their appearance resembles dark sonic but more jagged due to their premature body having to adapt and grow into mordern sonic as fleetway was classic Sonic originally,after awhile they found sonic but his reincarnation after many years in the timeline where silver was but silver is way younger now named latarios sezing the opportunity they bonded like a symbiote merging as one as latarios wasn't as fast or good enough as the original with the feeling of missing apart of himself now as one fleetway is now known as axiom

(This was kinda the original idea for them but this one is updated lore and fleetway is now added for plot reason ,I am not good at writing a story)