Xenogears. Before it, I never knew any game story could be so complex, entertaining, and deep.

Some great responses.

KEEP IT UP!

Playing Qbert in an arcade at 7 years old... 30 years ago.

in terms of visual fidelity and inmersion Goldeneye and Banjo&Kazooie
overall SuperMarioWorld is the GAME that made me a gamer

Maniac Mansion was the first game where i realized how great games are

Alone in the Dark and Realms of Arkania: Blade of Destiny in 1992 were the games which let me realize that this will be my addiction for the next decades. 

But i don't really have a game which changed my view on games compared to the games before, just like i mentioned above.

i guess games were just games until Valkyria Chronicles. before that game, i though of every possible tactical strategy possible in a game. so before VC it was about winning, beating, and strategy.

Hollywood Pictures. Most won't know the game, as it's just some Business Simulation from a german developer. Those Simulation games seem to be popular only around here anyway. But it really got me back then. I grew up with the NES an SNES and just knew action based games you could beat relatively fast. Hollywood Pictures changed that, as there is no real goal. You just keep on playing forever, trying to beat records, earning money and stuff. I played that game for YEARS. No kidding, even today I play it sometimes.

A game that had a similar appeal to me and will be known by more people would be Transport Tycoon. It's basically the same, you just keep on going forever, there is always something to do. But I played Hollywood Pictures before that and since then I'm hooked. Business Sims are my favourite Genre by far and it's a shame that there are so few games. Game Dev Story on Android is just too easy and lacks the deepness such a game needs. I also don't like Landwirtschaftssimulator (don't know the english name) all that much, it has too much graphics. Keep the graphics simple but the business part should be as deep and complicated as possible. I can even play with excel tables alone, there is simply no need for graphics in this genre. A good example is EAs FIFA Manager which basically hasn't any graphics at all, but I enjoy it a lot. Yeah, I know, many say Segas Football Manager is better, but I don't care for the football part all that much and miss all the business.

My personal dream is a Big Budget Title about console sales and console wars. You play some manufacturer and try to become number 1 in the market. I wouldn't need another game for the rest of my life. 

I could go on forever talking about business sims, as it's also hard to find someone else who is into stuff like that. But I'm just going to stop now. ^^

Ocarina of Time, truly a game like none other.

I had been a fan of Mario Bros. as a small child, but it was not until the year of Nineteen Hundred and Ninety, when my uncle bought "Dragon Warrior" which ended up being the game that changed the way I viewed gaming and solidified me as a core gamer. I never beat it until I was much older but for a kid who was five at the time, I was pretty damn good!

 Ahhh, the memories!

Legend of Zelda: Wind Waker -  The game that made my childhood.