This is the campaign I've made back in summer 2009 - "7 hours later". Old L4D fans should likely remember it. It consists of 5 maps with mostly forest scenery with the 4th map as exception (some industrial zone/bunker). This campaign also has L4D2 version but I'm not responsible for it, it was ported by another guy with my permission. I personally love the first game much more due to its atmosphere.
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