Bill (Left 4 Dead)

Bill is one of the four playable characters of Left 4 Dead. He is considered the most iconic of all eight Left 4 Dead characters, as he is the official leader of the original group.

Biography
William "Bill" Overbeck is a Vietnam veteran who was bitterly trudging through the last years of his life until the zombie apocalypse happened. The conflict of the apocalypse, while depressing, gave him meaning in life, and he met up with three other survivors, including Louis, Zoey, and Francis, before gunning their way through the zombie-swarmed Pennsylvania. In the campaign "The Sacrifice", Bill canonically sacrifices himself for the other survivors by pushing his way through a zombie horde, one that included multiple Tanks, to activate a generator.

Abilities and equipment
While Bill is avaliable to every weapon in the game, it's established he favors the M16 as a Vietnam veteran. Despite Bill's age and bum knee, he is still functionally identical to the other survivors.