Character(s):
The Emperor (villain); The Gladiators (the Emperor's henchmen); Gargantua (villain, first appearance); Professor Neilson (inventor of Leaper's suit, first appearance)
Notes:
Letters from Tom Stevens, Ed Zukowski, Jim Bridge, David Randall, Ralph Herman, Frank Paul, Gerald Wilhelm, Philip Goodrich, Ed Cermak, Steven Ensinger, Dennis Lykins, Robin Pelka, John Arlequin, Jack Joyce, and Cleveland Mason, Jr.