https://www.gamespot.com/articles/how-warhammer-vermintide-2-builds-on-left-4-deads-/1100-6457472/

Like its predecessor, Warhammer: Vermintide 2 for PC bears tons of similarities to Left 4 Dead. They're both games about holding off hordes of foul enemies while you head to safety. Survival is the name of the game for you and your party, and the game will throw all sorts of surprises at you to make that goal hard to achieve. But Vermintide 2 is more than a clone of Left 4 Dead; it goes the extra mile to make sure you are always on the edge of seat and that is a very good thing. Check out why in the video above.

Vermintide 2 even looks like Left 4 Dead 2 at times, with its same starting camera angles and chatter between characters. But Vermintide 2 is much less predictable; its AI does its best to continually throw new strategies at you. There is no sense of safety, making winning far more satisfying. Tomes and grimoires, which are rewards for risking rat-induced peril and exploring levels, also change the game considerably, adding extra layers of strategy and difficulty. Meanwhile, the diverse class system adds a huge layer of replayability that keeps things fun and varied.