Replying...
Intro. This story tells the continuation of the after escaping from the military barracks destroyed by zombies the survivors (Francis, Louis, Zoey and Bill) manage to escape on a military train from the chaos that was approaching the Millhaven military center the survivors manage to escape after arriving the survivors end up in a port area in Rayford Georgia where they look for a sailboat to flee to the islands of Cape Florida. You are Bill in the final chapter of this campaign you have to turn on three generators to lower the bridge and the other survivors manage to arrive when they activate the bridge the main generator fails and the bridge does not go up completely your role as Bill according to the story you must get off the bridge and activate the generator by sacrificing yourself and fight against the horde of infected and tanks although you manage to activate the generator the other survivors are safe above but you die giving them the opportunity to continue living

The sacrifice left 4 dead 2 ( el sacrificio de Bill )

@Ming