Sonic Frenzy Adventure
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Sonic Frenzy Adventure was born much before Sonic Worlds was a thing. The game was ambitious, with many fan characters, a huge story line and dozens of levels. Yet, the game fell under it's own weight.
Still, plenty of work was done and, after many years regreting not releasing it, I did what I should have done 10 years ago: deprecate the storyline, and pack all the levels as if it were a Sonic 2 style of game.
And here it is: a retro fangame (if that concept exists) with more than 10 different zones, lots of minibosses and several playable characters.