I got several that people have named already.
Mario Kart Double Dash. Took all the fun out of Mario Kart and replaced it with crappy gimmicks and lame tracks. The only good parts were the soundtrack, graphics, and kart designs. Good thing MKDS and MKWii brought this game back tenfold.
Xenosaga II. Battle system was insanely boring and unrewarding, and everything else about it was mediocre at best.
Grandia III. I disagree with Mercen-X up there, Grandia Xtreme was an awesome game with a refined battle system and lots of variety. So what if its story wasn't great? It's miles better than GIII's. Grandia III however suffered from Square-Enix syndrome: boring characters, many steps back in combat, hardly any story, and just an overall harrowing experience. All it has to its name are pretty graphics. Wooooooooow.
Devil May Cry 2. Nuff said. And yes, Dante is a lot more interesting than all these emo kids and traps running around in Japanese games these days.
King of Fighters 2001/2002. Neither lived up to the previous games and were IMO the black sheep of the KoF franchise along with KoFXII.
Metal Slug 3 and up= boring rehashed shooters crapped out to make a quick buck, basically. None of these except maybe 6 even came close to the fun factor of Metal Slugs 1 and X.
Final Fantasy XII. Worst. Final Fantasy. EVER. Everything went wrong here: shallow characters, slow-paced strategy-less combat, tediously long, no feeling of wanting to play the game again. Just had no soul.
Arc the Lad: End of Darkness. It took the good strat-RPG formula and replaced it with a very linear action RPG system with no variety. No thanks. I think I'll pass.
Xenogears is the tragic story of how your whole life can take a crappy turn, just because you happened to see a lady in a wedding dress before her wedding.
This boy is crackin' up, this boy has broken down
This boy is crackin' up, this boy has broke down
Dino Crisis 2. They had a perfect Resident Evil with dinosaurs going in the original, then turned it into a run of the mill third person shooter where you get points to buy weapons and ammo, and removed all else that made it difficult. While keeping the static camera and tank controls. Retarded.
Of course there's FFX-2, but I've learned over the years not to waste my breath on that pile of utter hog.
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