"Vengeance in Vietnam!" Part 1 of 2. Script by Steve Englehart. Pencils by Bob Brown. Inks by Don Heck. Cover by Ron Wilson and John Romita. At the conclusion of last issue's blockbuster battle vs. the Zodiac, Libra made a surprise announcement: "I am the father of Mantis!" Wow, what a shock to the Avengers and Mantis too! Libra says he met Mantis' mother during the First Indochina War. And after a local crime lord, Monsieur Khruul, attacked his home, he gave his daughter to the Priests of Pama to be reared. Is this fact of fiction? Either way the Swordsman isn't waiting for answers! He jumps in a quinjet and makes a beeline for Saigon to confront his former boss! But that turns out to be a disastrous idea. By the time Earth's Mightiest Heroes arrive in Vietnam, the Swordsman has been defeated and forced to talk about Mantis' upbringing! The vindictive monsieur and his minions go to the Priests of Pama's' temple and the killing begins. The frustrated Avengers once again arrive too late, but as shown on the chilling two-page final panel, battle is coming to Earth's Mightiest Heroes next issue…and coming in spades! Origin of Libra. Partial origin of Mantis. Cameo appearances by the Zodiac and the Star-Stalker. First 25¢ issue. Avengers Lineup: Black Panther, Iron Man, Mantis, Scarlet Witch, Swordsman, Thor, and the Vision.