If "hardcore" gaming is spending lots of time on a game, it's pretty funny. To me it seems people just go on the net and tell "I'm a hardcore gamer, bla casual bla shit game" to feel better than others or special in some way. They even tend to think they are "the real customers" and "the real market for games". What the hell. So people admit they have a problem (spending lots of time on games) but twist it to feel good about it. Well, then you are so serious about all this that you actually can be considered "hardcore".

I'd rather live with: hardcore gaming is setting up your own tough challenges (or go by achievements and trophies these days) and play a game until you get it. Not because you have to because you are "hardcore", but just because you like the game.

My definition stems from the actual definition of casual (imagine that): basically a game that is designed in such a manner that it does not have to be taken serious to enjoy the intended experience. Such games include all the games listed in the OP (Moster Hunter is arguable) and many more simply because they are designed to appeal to a wide audience. In order to do this they have to be accessible and fit many different lifestyles. Other games include: Halo, Call of Duty, Gears of War, God of War, Killzone, most shooters, most Nintendo games (a notable exception being Fire Emblem), and the majority of games in general.

Other games are designed inherently for people who are looking at games more for an experience (for lack of better words) than simply recreation and likely as a result demand more of the player in terms of time and effort involved. These are games such as RPGS (both Japanese and Western) and games that are rather difficult in nature.

The typical vagueness of the definition only lies from people taking the definition out of its scope to fit their intended purpose to essentially downgrade or defend the quality of the game. I do not feel casual games are inferior nor vice versa. They are not usually games that I enjoy simply because I'm a more serious person. Any core game can be enjoyed in a more casual manner and any casual game can still be played in a serious manner. Non-casual games can still sell well, though it is much more unlikely.

With that said, the argument should really be toward console manufacturers who decide to overly rely on casual at the expense of the core gamer. I understand that casual gamers are necessary for the success of the console; however, there really is no excuse for not diversifying the experiences that your console offers.

If it's made by Nintendo it's a casual game. Also, Petz and Hannah Montana games.

Damn! You sure put a lot of though into it. Also, you would be loved as a teacher, never giving anyone a grade below A.

While I agree with the general concensus that most games can be taken in a casual or hardcore manner. I personally feel there are some games that are casual no matter how much you play them. Wii Fit is a good example, even if someone train an hour a day everyday with Wii Fit, it would still be casual gaming to me.

^Now you're just trying to fool everyone.

Similar to what amp316 said, whether a game is defined as "casual" or "hardcore" is completely determined by the way a person plays it.

Playing Zelda in itself is pretty hardcore, but if you try a speed run or refuse to collect any heart containers, then it becomes more hardcore.

Mass Effect is also hardcore in itself, but if you use an online guide and play in the lowest difficulty, then it is less hardcore.

A game in itself cannot be casual or hardcore. The gamer's skill and time investment ultimately determines the hardcore level to the individual gamer.

Now a game can be universally "casual" or universally "hardcore" if a majority of people play it in that manner (FarmVille and Skyrim respectively) but it still ultimately comes down to the way it is played. it's all relative.

I don't really feel that most games can simply be "defined" as casual or hardcore.  I'll participate in your side experiment, but with a twist to represent my feelings on the matter.

A rating, 1-5, with 1 being most casual and 5 being most hardcore, will be given to each series.

Mario (platformers) - 3
Zelda - 4
Halo - 3
Grand Theft Auto - 3
Call of Duty - 3
Mario Kart - 2
Madden - 2
Uncharted - 4
Street Fighter - 4
Final Fantasy - 3
Monster Hunter -4
Smash Bros. - 3
Guitar Hero/Rock Band - 2
Gears of War - 3

As you can see, no 1s or 5s were given.  "Carnival Games" would be a 1.  Dungeon Crawl Stone Soup would be a 5(seriously hard game - Demon's Souls got nothin on it).  Most games find themselves somewhere in between.

To me being called a hardcore gamer is an insult.

There is an exact definition of Casual Games. It is the genre that includes brain teaser games and games created for short play sessions.

The origin of the term came with Namco's marketing for Pacman. The genre also includes games like Minesweeper, MS Solitaire, Frogger, and Freecell. Nintendo re-iterated the genre name to include its Brain Age series; and the industry uses it to define games like Farmville or Angry Birds.

If you are listing games like Super Mario bros. or Mario Kart, you are wrong on the factual level. The genre Mario Kart belongs to is racing. Super Mario games are platformers.