If everyone on the planet was either a zombie or a vampire. The zombies would eventually starve to death, freeze to death in place's like Russia or Canada or decompose in the sun slowly everywhere else.
The vampires would be able to feed on animals if need be. Would obviously just wait it out.
Also I thought this was deadliest warrior not deadliest warriors. 1 vampire vs 63 zombies?
-Surely if zombies took over the planet they feed on the animals too?
Also and more importantly, are you taking your meds?