Team Fortress 2 is bringing back all five of its original "Scream Fortress" maps in advance of a larger Halloween-themed update. The levels are available in Team Fortress 2 right now.
Anyone with the game (it's free to play) can find the Scream Fortress updates by simply booting up the game and joining a multiplayer session. The Halloween-themed maps feature undead enemies and new achievements.
Halloween is a big holiday for Team Fortress 2, so who knows what Valve has coming for this year's update. A typically overstated announcement says bringing back the five maps is meant to ease players into whatever terror Scream Fortress 2014 holds. Past editions have involved new events, new maps and, of course, hats.