Claire will have to deal with William Birkin one last time. Now fully mutated the monster has to be put down. Here’s how to kill the creator of the G-Virus. Once you place Sherry into the train grab the minigun, this is going to be your best friend. The fight begins with Birkin’s heart completely exposed with large eyes, this is your only target. Birkin will attack rapidly with the most fatal attacks being his ground pound and charge. The ground pound and charge are easily avoided as he’ll climb up the shaft to launch himself below and will start acting like a bull when ready to charge. Birkin is quick and has a long reach, so keep about 5” away from him and use that minigun. Chances are you’ll use up all the ammo before he’s dead but you should have other items to finish off the brute.