In Back 4 Blood, the zombies are called the ridden while the human characters are referred to as the cleaners - survivors who are in fact immune to the zombie outbreak and are clean of the devil worm parasite. The aim of the game is still the same as players work co-operatively to shoot their way through each act. Another obvious difference is the terminology. Overall, the graphics and textures are a great improvement. Download it now to give Valves Left 4 Dead 2 PC game a fresh, new horrifying sound & look. RELATED: Pokémon: 10 Ways Platinum Is Different From Diamond & Pearl Bilians L4D2 Sound & Music Replacement Mod v1.0 for Left 4 Dead 2. Fans expected the games to be quite similar, but there are also some major differences. Valve was responsible for developing the 2 titles in the series with Left 4 Dead 2 being over a decade ago. The game developers are now known as Turtle Rock Studios and are responsible for creating Back 4 Blood. The newest first-person zombie shooter, Back 4 Blood, hit the shelves in October 2021 and has fans reminiscing about the Left 4 Dead days.