Boros (ボロス, Borosu), also called Lord Boros (ボロス主, Boros-sama) by his subordinates, is the leader of the Dark Matter Thieves, a group of alien invaders who are responsible for the destruction of A-City. Like Saitama, Boros faces a self-imposed existential crisis, becoming too powerful that nothing gave him thrill anymore, opting to travel to Earth because of a prophecy saying he would have a worthy opponent.