Back 4 Blood is often called the spiritual successor to Left 4 Dead, but when it comes to originality, Back 4 Blood's Ridden win against Left 4 Dead's Zombies (also called Infected). The difference between the two is striking, and not just in appearances. The Ridden as a concept are far more creative and original than the Infected of Left 4 Dead.
When using zombies in media, whether it's in a movie, cartoon, or video game, it's tough to make them original. They've been done so many times as to become a trope, and no matter what kind of spin creators put on them, they still tend to be the typical shambling corpses that first come to mind when people hear the word "zombie." Therefore, most of their originality comes from their origins. Most forms of zombies come from either some form of magic or a disease that spreads throughout the globe. Left 4 Dead's zombies, made by the game's Green Flu, are one of the latter.
Back 4 Blood's Devil Worms, an extraterrestrial parasite, are the source of the game's terrifying Ridden. The term Ridden comes from the fact that the worms infest people's bodies and "ride" them in order to infect more humans and kill any immune survivors. A parasite certainly breaks the mold of either magic or infection that most zombie types typically have, and one from outer space is even less common.
How The Ridden Are More Original Than The Infected
Both Back 4 Blood and Left 4 Dead feature Special variants, ones that are mutated in order to better fight against humans, but there's a vast difference between the ones in Back 4 Blood and Left 4 Dead. While the Infected do have horrific Special variants, the Ridden go above and beyond in terms of bodily alterations. They add extra limbs, tentacles, grotesquely stretched proportions, and truly monstrous size. The Infected, although horrible, are somewhat tame by comparison.
The world of Back 4 Blood also doesn't look like the typical post-apocalyptic zombie-infested wasteland. In most modern zombie narratives, humans are scattered, unorganized groups who are just trying to stay alive and uninfected. Humans immune to the Devil Worms, known as Cleaners, have instead banded together in order to take back the world from the Ridden - they take a much more proactive role over the course of Back 4 Blood's campaign. They're actively fighting instead of just trying to make it to the next day, which is rare among characters in a zombie apocalypse.
How The Ridden Have More Potential Than The Infected
The potential of the Ridden also wins out against the Infected. There's only so much that disease can do, and even though viruses are known for mutating and adapting, it's hard to imagine them altering people's bodies as much as the Ridden seem to be capable of. The Devil Worms of Back 4 Blood are a completely unknown entity, one that is seemingly on a mission to exterminate humanity and alter the planet for its own ends, so there's no telling what kind of horrific mutations they'll inflict upon their hosts next.
In addition, The Ridden give Back 4 Blood more potential for story development than the Infected did to Left 4 Dead. The Devil Worms are a seemingly more intelligent force than the Green Flu, so there's far more that can potentially be done with them in the game's ongoing fiction. Instead of spreading aimlessly across the globe like a virus does, they have the potential to be an intelligent and strategic enemy that is a true match for the Cleaners working so hard to fight them back. The possibilities for the struggle between humans and the Ridden in Back 4 Blood are almost endless, making the prospect of future content an exciting one.