First, Lizard went up to unarmed players and offered them food and an unloaded gun, thus sparing them the customary 45 minutes of looking for weapons in empty barns. At this point, Lizard went "Whoops, I think I gave you my loaded gun, can you give it back?" About half of the players did exactly that, but the other half pointed the gun at their benefactor and tried to kill him. What those ingrates didn't know was that Lizard had jammed the gun before handing it over, and the only thing they were killing was their own dignity.
One player was offered a gun and acted friendly at first. It was only when he knew Lizard was checking his menu for food to give away that he figured he could get an easy kill.
After being caught out, he, like most others in this situation, felt compelled to run away in a mix of shame and terror.
To be fair, Cyborg Lizard did make a sequel wherein hardly anyone tried to betray him ... probably because they'd all seen the first video.