Dead or dying game series

Someone's going to say it sooner or later, so I guess I'll break it in. Sonic the Hedgehog.

Oh boy, this was such the bomb back in the day. Catchy music, easy-to-learn and perfectly-measured frustrating gameplay, a solid formula for a game that was at the time mostly unique. Something started to change around the Adventure games, though. Maybe it was the games themselves, maybe it was subculture, maybe it was me. I don't know.

Was it the games, entirely changing from the simple quick-reflexes side-scrolling to a 3D linear world explorer with a control scheme too fast for its own good? Was it the horrendously awful dialogue and character implementation? Was it the social cult following it generated? Again, I don't know, but I've told myself by now that unless something drastic happens, I'm never playing a Sonic game again, although I will hold the early memories fondly in my heart.