i have done some extra study on this demo...the only thing you need is better enemies (what im trying to say the people you kill,make them better in looks so they are like human not stick figure)
im going with firewalls idea about the turning humans into zombies...if they were minions and only lasted sertant time like 3 mins then they would just fall down to the ground and die
he might not have to time to even make the full version...if it took him a long time to make this then it would take a few years to make the full. ever thought of that?