Sonic 3 and Knuckles was my favorite Genesis game before I played Treasure's Alien Soldier and for good reason. Sonic Team did a rare thing here and actually learned the lessons from the development of Sonic 1, 2, and CD and gave us the most consistently fun 2D Sonic game. I think the game can trip up in areas such as Sandopolis zone, but overall it's easy to return to this game and have a good time where I don't revisit the other classic Sonics nearly as much, or even the 3D sonic games to be honest.