In 2012, Aliens in search of new habitats, wiped out the human race, mistaking them for just another pest on Earth. Their massive alpha particle weapons laid waste the planet, leaving them room to sow the seeds that would make the planet livable for them.
Upon returning years later, expecting a new haven, they found that those same alpha particles would over time turn dead human flesh alive. Dead humans were not what the aliens expected, and a new power struggle to claim lordship over the planet began… You are the commander! A Zombie Commander. Beat the aliens out and save Zombianity. After that you can unlock and become the Alien Commander and rule over earth. What would like to be?