Back in the 1980's, you weren't badass if you didn't have a "Rambo" Knife.
The movie First Blood introduced us to John Rambo, a Special Forces vet suffering from extreme Post Traumatic Stress Disorder, and some form of dissociative disorder. Pushed too far, the rugged individualist Rambo struck back with his survivalist skills. And he used his trusty Bowie knife to help him out.
The first two movies set the pattern for the pop-culture phenomena of the Rambo Knife. He used large Bowie knives with sawbacks and hollow handles. An assortment of survival goodies were stored in the hollow, including a compass under the cap.
The third movie broke the pattern by using a knife without the survival kit handle. But the knife was still over-sized and created as an artfully-shaped Bowie.
The recent sequel went further. The knife was the biggest yet, but the shape had changed completely into a Jungle machete or parang type blade. Also, while the other knives had been handcrafted by artisan bladesmiths, the fourth knife was intentionally left more crude and primitive to reflect the storyline of the movie. (The knife itself, of course was still handmade by a bladesmith.)
Above are replicas of these iconic knives. And while the Rambo knife has had critics over the years, any of them will serve you well in the inevitable zombiggeddon. Just make sure you're buying a quality survival knife and not a $15 Taiwanese import.