Two extraterrestrial species have haunted - and hunted - mankind throughout history: one a parasitic killing machine that uses humans as unwilling hosts for its lethal offspring, the other a relentless stalker that uses otherworldly stealth technology and weaponry to take men as grisly trophy kills. For over two decades, Dark Horse Comics has catalogued these terrifying contacts, harnessing the talents of a virtual who's who list of comics, science-fiction and fantasy illustrators to bring these tales to life.