[General Discussion] Question: What makes a game fun for you?

I like games with a medium difficulty curve.
If the game is too easy (Atelier Iris) or too hard (Unlimited Saga) then I won't be hooked to it, and it becomes more of a chore, completion-wise for easy games, and working with the little you have to go by for hard games.
Games that are medium or slightly above medium are just right for me, since you can manage them without too much difficulty, and they don't have any particularly annoying brain busters.
Hard games are awesome when several other elements are executed well (Disgaea) as well as open-ended games where the level of difficulty is up to you (Katamari, depending on your ultimate goals).



Although increasingly hard to find nowadays, an excellent story with plot twists are the jackpot.
The last time a story wowed me was Tales of Symphonia. There were multiple plot twists and they weren't all standard rpg fare. Granted, some might have found the ideas behind some of them to be cheesy, but even so, there were a couple of really great unpredictable ones mid to late game.



Various tasks for completionists is definitely a factor.
I love games in which there are so many tasks and sidequests and options you can take part it that will keep you busy for a while. I don't mean replay value necessarily, but rather a very long experience throughout the majority of the game is good. I like the idea of probably not being able to get everything without investing tons of time.



Finally, I don't think anyone will mention this, but overkill is my top criterion.
Best summed by examples:

Soul Calibur series, Virtua Fighter, KoF 2006 - You can hit your opponent over and over again after the round/match and in SC you can hear their screams.

Disgaea, Phantom Brave, NIS RPGs - spicy overkill attacks that are a far cry from the monotous swings of a sword or thwacks of a staff.

FF series - graphical overkill most of the time, especially summons-wise. Long winded and pretty animations are good, especially since they give usually proportionate rewards.

Tetris Attack, Puyo Pop Fever - long chain reactions give you verbal support, massive rewards, and flashy screen filling attacks. this also reinforces the idea of risk to reward which I also love. Longer chains leave you open to attack and give the opponent time to clear their field, but the reward comes in the form of massive attacks that your opponent will struggle with upon completion.

Jam it back in, in the dark.