Here, I'll give you a list. All of them are games that, while not necessarily bad, I find have made a strong negative impact on the gaming community's IQ or else have had a negative impact on game design as a profession.
The Executive Summary version:
Halo - You know why this is. If you don't, stop reading.
Zelda: Twilight Princess - Because we really shouldn't idolize the type of game that pretty much plays the same no matter what coat of paint you slap on it, and that's what the 3D Zelda games are.
Final Fantasy 12 - It just doesn't deserve to exist.
Kingdom Hearts 2 - Because I shouldn't have to endure the Organization 13 cosplay OR the roxas and axel porn.
Sonic 2006 - For sealing Sonic more thoroughly in his deep, ill-deserved grave. Thanks Sega. Thanks for making a game I as one of your fans would be embarrassed to be in close proximity with, much less to play. Thank goodness that of all the games on this list, THIS is the one I didn't buy.
Halo - A game I thoroughly enjoyed at the time when I was in the minority of people who bought Xboxes, but I dearly wish that some other game--Oddworld maybe--were the messiah of western gaming as I sit here in a game design program in college surrounded by halo-brained programmers who can't think of anything else and see "making the next Halo" as the ultimate zen of gaming.
The Legend of Zelda: Twilight Princess - If it's not Halo, it's THIS game series they're leaping at, and all of my projects have suffered greatly for it as we've tried to recreate the experience of playing Zelda in an engine ill-suited to the genre it represents. I don't think I even LIKE Twilight Princess, to be honest. Sure, there's imagination, but are we really going to idolize a game series that doesn't need US to play it? Has anyone paid attention to the fact that the puzzles practically solve themselves? It's more like a digital Rube Goldberg machine with a story than a game to me. A superbly polished Rube Goldberg machine with one of my favorite bad guys ever and a WICKED-looking sword to go along with him (why couldn't Link wield THAT?), but it just aggravates me that we try to re-create this at all when every offshoot of Zelda that can possibly exist is the same game with a new coat of paint. Thank goodness for Beyond Good and Evil.
Final Fantasy 12 - As long as we're talking about the same game with a different coat of paint, let's talk about a game that a lot of people LIKE to say is one of those but doesn't quite fit the mold. Nevertheless FF12 is quite pernicious. What distresses me about it isn't that it's the 12th of the series so much as the fact that quite a lot of people think it's good. It's the crowning proof that our standards for gameplay and writing have dropped through the floor and that we will buy ANYTHING if it has a tenured name even if it's wholly undeserving of it. Come on, FF fans. The developers openly admitted that Vaan and Penelo were a last-minute tack-on to the story to keep it "safe" for marketing. They aren't interested in making new stuff any more than I am in playing this game again, but at the VERY least they could peddle their garbage competently. It's an MMORPG without the MMO part, the worst balance issues I've ever seen in an RPG (summons = useless, quickenings = spammable death to all, and there's nothing to stop you from getting ALL THREE for each character before you even know what the story is about), and all of the pretty stuff that FF was renowned for in the past hacked right out. They just ROYALLY BLEW IT, and yet they still made buckets of money off of it and got perfect tens in the reviews. That reeks of injustice.
Kingdom Hearts 2 - Proof of more of the same. I can talk about the messy interface, how clunky that menu in the corner is; I can talk about how easy the game is; I can talk about how unimaginatively designed (albeit imaginatively drawn) the levels are; but what really upsets me is the massive story decay and the fact that Organization 13 is such a popular bunch of bad guys (and I use this term VERY loosely for them).
Do you know who a bad guy is? Ganondorf. A man who consistently turns kingdoms to ruin in whatever game he's in. The Joker. A man who NOT ONLY threw Gotham into panic and chaos but also a man who took Gotham's saviors and turned them both into its Satans. Men who do damage. In Kingdom Hearts 1, Maleficent turned Sora and Riku, two perfectly hapless victims of circumstance and best friends into bitter enemies, practically damning Riku's immortal soul to hell for the sake of her schemes. Ansem and the Heartless DESTROYED entire WORLDS, something that we got to see in all-too-disturbing relief at the game's outset as the main character's home is wiped out before his very eyes. THESE are bad guys.
Organization 13, as of Kingdom Hearts 2, put up the IMAGE of menace without actually being menacing as all of them consistently folded their arms over their chests haughtily and said to Sora, "don't you know who I am? I'M with Organization 13!" as if it were supposed to mean something after he and Riku managed to kill half their number in a prior game. In terms of net villainy they manage to delay the reunion of best friends for a while and confuse the hero with cryptic references to Roxas, who's ALREADY a part of Sora again by the time the game starts and therefore COMPLETELY inconsequential, but that's it. And what was their grand plot? To have Sora kill Heartless, which would have been considerably more successful if they just HADN'T BOTHERED HIM. Dumbest. Villains. Ever. Yet they're STUPENDOUSLY popular. This is our seal of quality? It's a story that may as well have not happened if the bad guys couldn't make a play at doing any real damage, yet we just eat this garbage right up. I wish this game had never happened if only so that I wouldn't have to endure the bad cosplay.