the touches on what i call the "reward feedback loop".

its seems that many games that aren't pure chance have a "reward feedback loop" as part of the basic game mechanic.

the player does something, and receives feedback. actions that move the player towards success in the game provide rewards.

this can be seen at both the micro and macro levels:

"reward feedback" at the micro level:

player turns left (action), car turns left (feedback), avoids hazard (reward).

player turns right by accident (wrong action), car turns right (feedback), player hits hazard (penalty).

as for the loop part:

1. player kills stuff to get treasure

2. player uses treasure to get gear to kill more stuff

3. goto 1.

when i was first designing Caveman, the loop was "find stuff to make stuff". This turned out to be too simple. So skills were added. So now its more like "find stuff to make stuff" and "find and make stuff to learn skills", and "find stuff, make stuff, and use skills to do things".

the point is that all fun games seem to have this reward feedback loop where positive actions on the part of the player are rewarded. and a multi-step loop ( do A to get B to get C which make you better at doing A) seems to make for a more interesting game. OTOH, arcade shooters are fun , and sometimes just have a simple, "hit something - increase score" type reward feedback loop.

I have several posts trying to get to the root of games in general. This was the reason for this post:

http://www.gamedev.net/topic/652775-whats-in-a-game/

and this one:

http://www.gamedev.net/topic/650786-any-game-makers-here/

If I can go back to what I considered fun as a child, usually when I was having fun, I was laughing and feeling exuberant.

This is a decent definition of game from a google search:

"a form of play or sport, esp. a competitive one played according to rules and decided by skill, strength, or luck."

So combine that definition with good game mechanics that create that child-like exuberance and you have a fun game.

A fun game is one where repetition does not feel boring. Everything in life is about sufficient repetition; therefore, the most important aspect is to make the repetition of the game interesting and immersible.

Graphics is the "bait" and content (what the player can do) and the story is the "hook" of a game (for me). My two latest favorites are Fallout3 (also Fallout New Vegas) and Skyrim. They both have great graphics, but what makes them worth playing over and over again is the sheer volume of content available to the player. I find myself wanting to start over just because of the challenge of staying alive long enough to develop my character to the point that it's no longer a challenge.... Vicious cycle....

So, I think the most interest for me is the survival challenge. Scavenging, avoiding obvious dangers, collecting necessary supplies, etc...

This is very similar to me. Skyrim's story wasn't really my cup of tea, and that's the only reason I haven't replayed it yet. But I would jump all over a Skyrim clone with a different genre of story (no horror, more romance-fantasy-adventure). I'd probably scream with frustration if it still had the two MAJOR design problems that drove me crazy in Skyrim (mount not shown on radar and unkillable NPCs) but I'd play it anyway.