Back 4 Blood is a cooperative shooter that puts a heavy emphasis on teamwork. As you fight your way through the hordes of Ridden, you will need to rely on the other Cleaners as much as they will depend on you. That being said, should you be more careful when firing when teammates are on the screen? Friendly fire is one of the most aggravating ways to die in a video game, so can you kill teammates in Back 4 Blood?
Back 4 Blood’s friendly fire will depend on what difficulty you are playing on. If you are playing on Survivor, teammates shot by you will yell at you about the friendly fire but will not take any damage, making it impossible to kill them. However, you will deal increased damage on any of the higher difficulties, with the highest level taking significant chunks of damage with each bullet making an impact. Veteran has 35% friendly fire, and Nightmare has 60% damage. With healing items in short supply, you want to avoid this at all costs.
This is similar to how Left 4 Dead handled its friendly fire back in the day, so if you played those games, you will have a general feel for how the game handles teammate damage. If a teammate is grabbed by a Ridden, you have a little more leeway in shooting near them to get them free. The game will transfer this damage into the enemy holding them.