Volume 21 (Dark Horse)

Volume 21 is the twenty-first volume of Astro Boy released in the US.

Published by Dark Horse, this reprint collection follows the Tezuka-designed order first used in the Japanese Akita Shoten collections, as opposed to the original Shonen chronological order used by Kodansha in their Osamu Tezuka Complete Manga Works series.

Chapters

 * Robot Bombs
 * Mission to Mars
 * Sea Serpent Island
 * Frankenstein
 * The Coral Reef Adventure
 * The Test Pilot
 * Super Cyclone