2/3 of them are references to

Sonic's Concept and is also a Skin in Sonic Superstars Cream's Debut (Though inconsistent looks)

A former 90s rival's (A red capped plumber guy) recent 3D platformer since 2017

I'm taking you down like its 1998/1999!

Act Music as Rounds? (may not apply to every stage)

Silver (With A Counter move with a cost of Power) and Metal Sonic

(Not finalized yet but its a resemblance.) I have decided to make it 3 Buttoned. Though the Basic attacks mapped A,B and C buttons will also be mapped to X,Y and Z

So far. The Super Transformation is far from completion. (Super Sonic Sprites by "TheKnucklesMainG4")

Giving the character's Icons some polish.

(Will be in the next update)

(Silver Update)

Another Trap attack + A returning move from Infinite Battle + And another intro

Despite being Water (Or Mutated Chao) slime sounds

That Hover Move.

It's like the OG game but less stiff.