I'll second StarFox. Ninty never really did know what to do with this franchise. While most of the games in the series are "good" even Assault and Adventure and ... what was the DS one? Anyway - there is considerable debate as to whether most of them constitute "StarFox" games.
I'll also second Sonic.
And yeah, Final Fantasy is a series that has been by now mostly garbo. FF's I-VI are solid. But by VII the series began skidding into the trash pile. Now, FFVII isn't "bad" per se but it is by far the most overrated video game ever. Yes, even more overrated than Metal Gear (pick one). VII was not revolutionary. It was exactly the same Final Fantasy game as before with crude rudimentary 3D models on mostly 2D backdrops and Playstation's FMV scenes. Guys, this might come as somewhat of a shock to some but a movie is not a game.
From then on with the exception of IX, which has trash gameplay but a good story, and XII which has a great story lamentably weakened by executive meddling and garbo gameplay until the Zodiac version happened, the Final Fantasy series has been unmitigated slop and that includes the MMOs as well. The trashiness peaks with the XIII series. Although I actually rather admire XIII-2 on its own. VIII isn't far behind and X is the kernel of a good idea quickly turned into a pathetic joke. XV is just lame. Lazy. Unimaginative. Derivative. Disappointing. Dull.
For Final Fantasy you'll have somewhat better fortune with the spinoff series. Tactics remains solid but everything having to do with VII are just shameless cash grabs. Why Chronicles is still not a thing anymore is sad but while that series had potential it could have been so much more and is thus highly overrated.
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