As promised

Ever want to play as the aliens in X-Com? Well you can!
"Ufo: The Two Sides is a multiplayer remake of the original game X-Com: Defence / Ufo: Enemy Uknown, developed by Mythos Games and MicroProse in early 90′.

Ufo tts recreates most of the original features, adding a couple of new ones, and changing ones that existed. However, the game recreates most of the features as faithfully as possible to maintain the unrivaled game-play of its predecessor. Although numerous other attempts have been made to recreate x-com defense, there is no (known to us) multiplayer game that lets you play full campaigns (that is both geoscape and battlescape). Project has been started on 1st of march 2009. There is no known date as to when it’s going to be complete.
All games from the ufo/x-com series are property of their owners (in 2005 rights have been aquired by Take-Two), the game is still being sold, therefore original game is not ‘abandonware’ and cannot be distributed for free legally. Presently Ufo: tts uses original graphics taken from ufo 1, making it impossible to be downloaded as a complete stand alone product. The crew is currently working on remaking all the graphics, so this will not be a problem in the future."



You will need a working copy of X-Com to play this as it is more of a MOD due to legal concerns.
They are working to change this by reworking ALL of the graphics, take a look at some of their work.

New Geoscape.

Updated base graphics.

A look at the alien base screen.

 
More info about the game.

"If you’re visiting this page, you most likely know the original game that Ufo: TTS is based upon. Therefore, the features listed here are only what will differ between both games. This list is by no means complete, as there are many more little details.

• Multiplayer – One person plays as humans, the other plays as Alien Invaders
• Singleplayer as either of sides. You can finally play as Ufo even in singleplayer mode
• Geoscape time passing in tactical combat – see day become night or the other way around.
• Rebalanced and reworked tactical combat. Its no longer as much luck based as it was. Its more about tactics, positions and using some of the previously not popular items (smoke screen for example will be more useful)
• Reworked air combat making it possible to engage 4 vs 4 crafts at a time. Also, air battle is now determined not only by range of weapons, but also by speed of the craft. Even if you equip long distance weapons, you cannot hold enemy crafts away for infinite time.
• Keyboard shortcuts
• Small, yet interesting changes to races, mostly to give them more combat flavor, instead of just ufopedia flavor. Remember reading Celatid’s description? Their flavor text mentioned they can detect human brain waves. Celatids in Ufo: TTS will also! Making them act like a radar for Muton soldiers.
• Alien ranks gain more meaning. Medic will finally be able to help his mates.
• Game works on XP and VISTA (of the tested systems. Might work on other windows family systems)
• many, many more…"

Game art.

More game art.

It is still in development but I look forward to the finished product. This is completely free so if you do own a copy of X-Com it's worth checking out. After all who doesn't like playing the bad guy every once in a while?

Check out their project page http://ufotts.ninex.info/