ChaosX aka the guy who made Project 06 made a mockup fan version of Sonic Frontiers before the IGN gameplay showcases came out.
Here's some old gameplay of it, 1st newer and 2nd older.
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Here's a updated screenshot of the game, it's not playable right and still very wip right now as of my knowing.
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It seemed to also be made around the Sonic Forces engine or at least it was frame work for it, don't know what he's going to do when it comes to enemies or if there will even be any.
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He's still working on and added a playable SA1 (Dreamcast and DX) Sonic as well, it's a pretty neat project but I'm now wondering though if he'll do anything more with this project especially cuz of the current situation with Frontiers.
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