You only get 30 seconds. Go!
- Command and Conquer
That's all I can think of. Seems like every other games I really loved were never made into franchises, and were mostly just one offs or had one sequel and it sucked. Looking at you Dragon Age 2. If you want to pretend DA2 was never made, and still had hope DA3 will be good and not just another DA2, then I guess that.
Sonic (I grew up with this franchise...so...shut up)
I'd love to throw in Beyond Good and Evil but Ubisoft is full of a bunch of mother-fucking pieces of shit who use the second game in the series as a baiting tool to get people to buy games and, as such, haven't released the second game because then they wouldn't have anything to hold over the head's of their fans. Thus there really isn't a franchise.
1. Super Mario Bros. (platformers)
2. The Legend of Zelda
I hate it, but it's the truth. Most other franchises have one game I absolutely ADORE and other games I either haven't played or don't care for. I really dislike Ocarina of Time, but everything else is super fuckin' awesome in those franchises.
EDIT POST-30 SECONDS: Metal Gear Solid and Assassin's Creed are close, but the fourth title in each SERIOUSLY hinders each. I really like what I've played of Mass Effect and GTA, but that's really just two titles and not quite a franchise.
1.Mass Effect (Though it feels strange putting it on after only two games)
2.Shin Megami Tensei
3.Call of Duty (Yeah I know but I've had so much fun and spent so much time with this series over the years I wouldn't keep coming back to it if there wasn't something there.)