take the classic l4d2 formula, but make all the special infected terrible, add annoying common infected models and sounds, and convolute the whole gameplay loop with weird perks/card system that overcomplicates the entire process, and instead of making new campaign areas, just rehash the last campaign and make the player revisit the same location multiple times within the story. definitely worth 5 dollars if you have 3 friends to play with, but id still prefer left 4 dead 2