Remember that all the fun you had playing that zombie video game where you played as two zombie-killing sisters, one clad in a catholic school girl outfit and the other dressed in a bikini, cowboy hat and feather boa? Of course you don't.
Oasis of the Zombies was written and directed by Jess Franco, a Spanish director of over 100 films and self-proclaimed hater of zombies ("they're stupid" he says in a DVD interview). So why did he have to go write and direct a movie about them?