RELATED: 10 Short (But Scary) Horror Games Worth Playingįor this list, we are counting down the timeless and most well-made maps that keep players coming back for more. Left 4 Dead pioneered the zombie FPS genre and even after a decade, the franchise remains unbeaten thanks to the veterans and modders who are keeping the title alive through wacky add-ons and mind-blowing speedruns. From Half-Life to Dota 2, the company has enjoyed a streak of good luck, and for good reason. Valve has one of the most loyal fanbases in the gaming industry. The Left 4 Dead series has immense replayability, especially given that modders add to the already fantastic campaigns provided by the game.