Avengers, The (1963 series) #10

1st appearance of Immortus

The Avengers consider making Rick Jones an official Avenger this issue, but Captain America is wary of leading another powerless teenager (after Bucky) into danger. Rick falls into Immortus' trap because he is seeking a power to make him worthy to be an Avenger. Immortus is introduced here as the master of Limbo. He will turn up many times, with his own agenda that makes him sometimes appear to be a bad guy, sometimes a good one. In Giant-Size #3 we will learn that he is a future version of Kang. Avengers Forever will attempt to sort out the complicated history of this combined character, and will end up separating them into 2 distinct beings. The Hercules seen here is very different from the one who will debut in Journey into Mystery Annual #1. This version of Merlin may also not match any of the Merlins seen elsewhere. The latest Avengers Index follows the theory espoused in Avengers Forever that the characters conjured up by Immortus here are actually played by his servants the Space Phantoms. We met our 1st Space Phantom in #2. We will see a whole planet-full in Thor #281-282. However a Space Phantom impersonates someone by banishing them to Limbo. #2 established that a Space Phantom couldn't do that to a god like Thor. Thus they shouldn't be able to impersonate Hercules (or possibly even Merlin). Earlier versions of the Index suggest that the characters here are played by Dire Wraiths, banished to Limbo by Rom and the SpaceKnights. I think this is the 1st issue where Zemo, Enchantress and Executioner are referred to as the Masters of Evil. Previously the name was only used for Zemo's band of villains in #6. the current trio didn't use the name in #7 and #9. The trio won't be seen again until the combination of both groups as the Masters of Evil in #15-16.