>>718117096 (OP)
Probably Sonic 3 & Knuckles. It's a solid experience. Best modern game, probably Sonic Adventure 2, warts and all. The speed is manageable, the combo aspect of the Tails/Eggman stages is fun, the only downside to Knuckles/Rouge stages is the lack of targeting for nearby objects and the fact that only one of the three emeralds beeps at a time when in Sonic Adventure that wasn't the case. Sonic Heroes is too repetitive, Sonic Adventure contains entire stages rehashed with characters in a way that's less fun, Sonic 06 was a disaster, and Sonic Unleashed was too unforgiving. In earlier Sonic games if you fucked up, the punishment was a lower, slower pathway. In Unleashed, if you get it wrong, fuck you, lose a life. There's no flow to it, but I respect the insane speed it has, people that love that sort of challenge must have been thrilled when it was new. Unfortunately, it's dragged down by the extremely tedious Werehog segments.
So yeah, it's not a great game, but by default I feel like Sonic Adventure 2 wins out. The big issue is that Sonic games need to be at least six hours, so not having it all be Sonic stages makes sense if you can learn to like the other characters and their playstyles. I don't know why they never bothered to make another Sonic game that builds on Adventure 2, there's so much room left to explore and improve upon the core design. Sonic segments can be like always, fast and arcade-like. Tails' levels can be like Armored Core 6. Knuckles' levels, instead of being emerald hunts, can be the most platforming heavy because come on, he can fuckin climb on walls. To get chaos emeralds, all three segments need to collect enough rings and hold on to them to finish and then that unlocks the special zone levels where Sonic races against Eggman to get the emeralds. Bring back Rouge as a bad guy who only works with Eggman for the money, and then a new robot character to square up against Knuckles.