The Lucario, Luca, starts by telling us about how the plague began. Mad milktank disease mutated and created Patient Zero. Patient Zero spread the plague until most of the world was wiped out. Luca survived because he was a bit of a shut in. His neurosis peaked at college and so, when the plague hit, he stayed indoors mooching off of pizza, Mountain Dew code red and playing Pokémon (though he is one). So be his partner and kicks some Zombie ass (plus he's built...he's hot)