X-5. X-5 is a top secret agent for the U.S. government. Later on he went by "G-5, Super Agent."
First Appearance: Hit Comics #1 (Quality)

Yank. Rick Walters is the son of Walt Walters, aka The Black Owl. Unfortunately, Rick and his twin brother Dick are too young to officially enlist, so they put on costumes to fight enemy spies in the U.S., Rick as Yank and Dick as his partner Doodle. Yank is almost powerless when alone, but when he is in the presence of the Doodle he has superstrength and invulnerability.
First Appearance: Prize Comics #13 (Prize)

Yankee Boy. Victor Martin is an ordinary teenager who just happens to put on a costume and help Inspector Foley fight crime.
First Appearance: Yankee Comics #2 (Harry “A” Chesler)

Yankee Doodle Jones. YD was a patriotic hero. He was helped by Dandy.
First Appearance: Yankee Comics #1 (Harry “A” Chesler)

Yankee Eagle. Jerry Noble is the "light-hearted," prank-loving, independently wealthy son of a Senator who is inspired to fight German saboteurs out of love of country. He has no superpowers but is relatively cunning and is helped by Sam, his pet eagle.
First Appearance: Military Comics #1 (Quality)

Yankee Girl. Jakeoster contributes the following:

The blonde superheroine was actually a "shy settlement worker" named Kitty Kelly.

Yankee Longago. George "Yankee" Longago is a boy who travels through time, meeting Amazons and the Pirate Prince and Crimebuster.
First Appearance: Boy Comics #3 (Lev Gleason)

Yankee Girl. Laura Mason, the teenaged member of society's Junior League, learns some old arcane knowledge and gains the power of changing into Yankee Girl just by saying the words "Yankee Doodle Dandy." She can fly and is mostly invulnerable.
First Appearance: Red Seal Comics #17 (Harry "A" Chesler)

Yarko the Great. Yarko the Great is both a stage magician and a real one, and he uses both sets of abilities to fight crime.
First Appearance: Wonder Comics #2 (Better)

Yellowjacket. Vince Harley is a crime writer looking for information on the perfect crime. In his search he becomes involved with a bank robbery. The thieves knock him out and then try to tip a carton of yellowjackets on top of him. However, Vince is not stung, as he is “one of those rare people that bees don’t sting.” Vince is not stung, but is angry, and so puts on a costume, discovers his talent for directing bees, and goes out and fights crime. He has the ability to command bees and brings swarms with him on patrol.
First Appearance: Yellowjacket Comics (Frank Communale #1)

Young Allies. The Young Allies were a kid gang brought together by Bucky and Toro to help fight crime while they were free from helping their older friends. The Allies were, in addition to Bucky and Toro, Knuckles (the Brooklyn tough guy), Tubby (the fat kid), Jeff (the bookworm) and Whitewash Jones (the racist stereotype).
First Appearance: Young Allies #1 (Timely)

Young Avenger. Bill Bryon, an average American teenager, is awoken from a sound sleep and given instructions by the voice of a shadow, which directs him to where the bad guys are. Bryon then puts on the Young Avenger's costume and goes out and beats the bad guys. In the story Bryon already has the Young Avenger's costume and powers, and it's implied that the Young Avenger has been directed before by the shadow. No other origin is given for the Young Avenger, however. He has superstrength.
First Appearance: USA Comics #1 (Timely)

Young Defenders. The Young Defenders are four children named Lefty, Slim, Whitey, and Joanie. They are the adventurous sidekicks to Captain Freedom.
First Appearance: Speed Comics #32 (Harvey)

Young Robin Hood. Billy Lackington wants to help the war effort and eventually strikes upon a means of doing so. He decides to follow the model of his hero, Robin Hood, and begins fighting for justice and the right with a bow and arrow as Young Robin Hood. He is helped by a modern version of the Merry Men; Billy’s men are Fatso, Squeeky, and Freckles. Billy in turn sometimes sidekicks for Bombshell. Billy is a good archer but has no superpowers.
First Appearance: Boy Comics #3 (Lev Gleason)

Zago. Zago is a Tarzan clone with all of his skills. He is helped by Wana, his Sheena-like mate.
First Appearance: Zago, Jungle Prince #1 (Fox)

Zambini the Magician. See The Miracle Man.

Zanzibar. Zanzibar is a stage magician who uses his mental powers to fight crime. He's got telekinesis, mentally-powered superstrength, and hypnosis/mind-control.
First Appearance: Mystery Men #1 (Fox Features)

Zara. Zara, a white woman, was brought to "the jungle" by her father, who had "tired of crime-ridden civilization." He raised her there and taught her various skills, and as he was dying he told her to not let evil flourish in the jungle. She didn't, of course, helping various a great white hunter type and a group of "good natives" against the "bad natives."
First Appearance: Mystic Comics #2 (Timely)

Zardi. "Zardi, Prince of Zandipore, the Eternal Man...he saw the pyramids built--he saw the Red Sea parted! He knows every form of magic! The story long whispered among world explorers--that an eternal man exists after having lived for many, many centuries has been proved true! That man is Zardi, Prince of Zandipore, the Eternal Man!" He is immediately served by his Indian servant Nogi but has a vast network of helpers to assist him; they are around the world and are contacted telepathically by Zardi when needed. Zardi is fabulously wealthy, apparently having used his years to accumulate great stores of gems.
First Appearance: Amazing Man #11 (Centaur)

Zatara. John Zatara is a famous stage magician who actually has magical powers. Speaking his backwards spells, he travels the world, fighting evil and wicked magicians wherever he finds them, including his "loving enemy" the Tigress. His power is his magical ability; he can do anything with his spells.
First Appearance: Action Comics #1 (DC).

Zebra. John Doyle is a criminal lawyer who is framed by politicans and sent to jail. He breaks out and clears his name. Having successfully done that, he keeps the costume he wore while helping himself and decides to continue fighting crime as the striped Zebra. He has no powers, but is a good fighter.
First Appearance: Pocket Comics#1 (Harvey)

Zegra. Zegra began as a rewritten Rulah story but eventually became "Tegra," an otherwise undistinguished Sheena clone.
First Appearance: Zegra, Jungle Empress #1 (Fox)

Zephyr Jones. To quote from Daring Mystery #2: "Zephyr Jones is the son of the well-known scientist and inventor, Dr. Morrison Jones. Zephyr is following in the footsteps of his famous father who started building the rocket-ship with which he planned to visit the planet Mars. Dr. Jones unfortunately did not live to see his spaceship completed and his dream realized. Through mysterious circumstance he met his untimely end, and young Zephyr swears that he would fulfill his Dad's wishes and undertake the fantastic voyage to Mars." Naturally, Zephyr did go to "Mars," which was full of winged humans, and he (naturally) wooed the Martian princess, and then left to return to Earth. Zephyr Jones had no superpowers but was a doughty fighter and did have his spaceship.
First Appearance: Daring Mystery Comics #2 (Timely)

Zippo. Ronald Byrd saith:

We're moving into super-power territory with Zippo, alias p.i. Joe Blair. Zippo has low-level super-speed (that is, he can catch up with a speeding car but can't outrace a light switch or run across water or anything), evidently thanks to his costume...which has wheels for feet.  That's right, Zippo has wheels for feet.  We never see him in costume while at rest or moving at a normal speed, and as I try to summon such an image I realize that may be just as well.

ZL, ZR, and ZY. These three men, former FBI agents, are the assistants of the Masked Marvel and help him in the war against crime. They have no superpowers, but make use of the Marvel's equipment and guns.
First Appearance: Keen Detective Funnies v2 #7 (Centaur)

Zoro. "'Mystery Man' is his name and 'Mystery Man' his nature...all wonder who he is, none can tell...brilliant, courtly, enigmatic, able to fight like a devil and plan like a genius, he rights wrongs and smashes evil for the sake of the adventure, always remaining the Mystery Man." He's obviously a wealthy gentleman, he carries a sword cane, and he has a pet cheetah. He doesn't seem to have any actual superpowers, however.
First Appearance: somewhere in Slam Bang Comics (Fawcett)

ZX-5. ZX-5 is among America's best spies. Directed by Major Jason, ZX-5 roams the US and the world, first fighting Germany analogues and then Germans themselves. After the war he becomes a top private eye. He has no superpowers, but is otherwise so excellent that he needs none.
First Appearance: Jumbo Comics #1 (Fiction House)

Introduction
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