"We’re really excited to finally be able to show this major project we’ve been secretly working on since the release of the game. This is Dying Light from totally new angle, but with everything fans love about the original still at the core." -Tymon Smektala, Producer, Dying Light
Techland will reveal the new DLC behind closed doors at Gamescom in August, and share the news with the rest of the world soon after. As very little information is available as of yet, there is no saying if the upcoming content will be a part of the season pass or not, but it is fair to assume it won't be a free one.
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I call shotgun! Who else would like to speed through masses of zombies in a car?