One of the best things about video games is getting to unlock new items.

Achievements are an extension of this.

You are constantly rewarded, which just keeps you playing longer in the hope of earning something else.

Tokyo Game Show 2009 Opens To Press And Game Industry

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And it all adds up into a neat and tidy gamerscore that you could share with your friends.

What Makes a Game Good or Bad for Your Gamerscore?

Here is a listing of the best and worstXbox 360 gamesfor improving your gamerscore.

It also includes a listing of the games with the most difficult/ time-consuming/ ill-conceived achievements.

Games With Difficult or Time-Consuming Achievements