The lights are on
Commanding the aliens in one-on-one deathmatches in Firaxis' upcoming tactical strategy game is a very different experience than defending the Earth from their ravages. I recently had the chance to go mano-a-mano for a few rounds of XCOM multiplayer as Firaxis pulled back the curtain on the mode for the first time, and being on the giving side of a Muton Berserker's charge is definitely better than being the receiver.
Much like tabletop wargames, such as Warhammer 40,000 or Necromunda, a multiplayer XCOM match has each player filling out their squad to a preset point total. A quick game might only allow for a handful of moderately powered squaddies and/or smaller aliens, while a larger brawl could feature several godlike units on each side.
Aliens cost a fixed amount per unit, which scales to their power. A sectoid doesn't cost much, but the terrifying chrysalids, cyberdiscs, and worse eat up your budget quickly. XCOM soldiers, on the other hand, can be customized to nearly the same extent that they can in a single-player game. You can load down squaddies with any of the armor, specializations, weapons, and inventory items in the game – but a soldier rocking the best stuff a fully funded XCOM organization can provide costs far more than even the toughest alien.
Once you're in a match proper, it's just like any XCOM mission except that the bad guys have a human mind behind them. Each unit can move and take an action (or double-move) each turn, and the game is over when one side is completely wiped out.
Fog of war is as important a concept as it is in single-player. Each team starts in a randomized position on the chosen map (the build I played had a half-dozen available settings), and you have no idea what kind of units the other guy brought until you see them. Scouting, lines of sight, and cover are just as mission-critical as ever.
Because multiplayer retains the same full-team turn structure (all my guys go, then all yours, repeat), making sure first contact doesn't leave your squad exposed is hugely important. Multiplayer is just as lethal as single-player, meaning one bad turn can leave your team crippled or worse. Making sure your units are advancing cautiously and covering each other is paramount.
The turn timer's default two-minute setting is awfully short, especially with larger squad sizes. Attack animations alone can eat up a huge chunk of your allocated time, and I found myself forced to skip actions on a regular basis in larger skirmishes.
The overall structure of multiplayer in XCOM: Enemy Unknown is dirt-simple. There are no leagues or persistent rankings of any kind; it's just single-shot one-on-one deathmatches. Nonetheless, you finally get to control the aliens themselves. That's worth something all by itself.