Marvel's Avengers is now here for everyone to enjoy! The new game from Marvel, Square Enix, and Crystal Dynamics that's been years in the making can now be played by people all around the world. But if you're already feeling like you're playing catch-up thanks to some folks who had Early Access to the game, don't worry. Not only is Marvel's Avengers a game for the long haul that will continue well after the initial story campaign, we've also got some pro tips for you to help make your leveling-up process …