I've talked before about the motivating power of nostalgia among gamers, both hardcore and casual, old and young. There's just something about the history of video games that gamers are drawn to, whether it's plugging in an old console or firing up an emulator to play those classics in their raw form, or building on the foundation of those classics with remakes, sequels, and homages. Thanks to the classics, we get the best-selling Donkey Kong Country Returns (building on the foundation that started with Donkey Kong), Sonic the Hedgehog 4 (a new chapter in the long-running Sonic saga), and even a Joust themed section in the latest World of Warcraft expansion, Cataclysm (complete with all the button pushing exhaustion that the original brought players).

Recently a new tradition has appeared in the gaming world: looking at those classics from a different point of view, or modifying the original game in such a way that it still pays tribute to the original game, but adds a wild factor that we, as kids, could only dream of. The nostalgia factor is still high in these modified games, but they bring a cool "what if" element to the game, either looking at things from the other side or injecting new elements.

My favorite of these kinds of new creations is Super Mario Crossover, an emulation of the original Super Mario Brothers with a twist: new characters. I grew up with Super Mario Brothers and, while I don't remember ever having the discussion with my friends, a dialog about what you could do in that game world if you had Simon from Castlevania or the titular character from Mega Man seems as natural as debating whether Batman or Superman would win in a fight. Of course, that would never have happened in an era where game developers were super-protective of their characters, but this fan-made game allows that crossover to happen. The player makes their way through the virtual world of Super Mario Brothers but instead of playing as Mario or Luigi you can play as Simon, Mega Man, Link (from Legend of Zelda), Samus (from Metroid), and Bill R. (from Contra). An expanded version of the game has added Ryo (from Ninja Gaiden) and Sophia III (from Blaster Master).

As any of the alternate characters, you get abilities inherent to that toon: Mega Man, Samus, Sophia III, and Bill R. shoot firearms, Link and Ryu have a sword and Simon has his whip. Additionally, some characters have access to special abilities, like Mega Man having his slide move and the ability to charge his gun or Samus switching into a ball and planting bombs. Best of all, the game lets you switch between the characters after each death, so if you choose Simon and then discover he's not the character you really wanted to play you aren't locked into him for an entire game.

One of the more recent nostalgic twists to come my way is Space Defenders, a game that tries to answer the (unasked) question, "Why were the Space Invaders here?" Brief cutscenes reveal that Earth originally attacked their home planet, and the aliens have come here for revenge. During the actual gameplay, the player controls the invaders this time, raining bombs and terror down upon the cities below. You start with a small squad of aliens, targeting only the people down below. As levels advance you get a bigger squad, but the enemy gets bazooka turrets, missile silos, tanks, and more.

Space Defenders is a simplistic game, but so was the original Space Invaders, so a follow-up that looks at the game this way feels appropriate. It's kind of fun to play the enemy for a change, destroying the cities below instead of defending them. Unfortunately the game is a tad bit buggy. I experienced a ridiculous amount of lag as the levels progressed, with no real reason why. Still, it's a fun little time-waster with a nice nostalgic connection to the past.

Although these are just a couple of games with this sort of nostalgic twist, they provide a foundation that makes me curious about the future. What other sort of game may be in the works from classic game fans? A Pac-Man alternative where you control the ghosts and try to chase down that dreaded chomping ball? A Mario strategy game where you place forces in Mario's path? Any of these things are possible because, as Super Mario Crossover and Space Defenders show us, our only limit is player imagination... and possibly some copyright laws.

Play Super Mario Crossover at Exploding Rabbit.com

Play Space Defenders at JayisGames.com