Gunther is met on the first level, "The Tower", and in "Compound" level. He serves as an access character to War mini-game.
He is again seen in "Harbinger" level, being captured, imprisoned and stripped off his cards. When B.J. encounters the Harbinger of Doom, the demon summoned by Nazis to aid them in war, he founds out that there is no way to harm the demon. The Spy advice B.J. to look for Spear of Destiny. Soon, Gunther appears, escaping his cell and revealing that he has already stole the artifact. Thankful to B.J. for playing cards with him, he handles the final weapon to B.J. so he could defeat the demon.