Tabu. To quote from Tabu's first appearance:

Deep in the heart of the jungle reigns a man with a sixth sense...according to legend, Tabu once saved an old witch-doctor from a terrible jungle death...and in return for the favor the witch-doctor gave Tabu an extra sense, which made him supreme in jungle-land. This sixth sense has made Tabu's instincts so keen that he excels over all animals. He can run faster than the deer or antelope, he can climb among the trees more agilely than any ape. He can stalk through the dense jungle grass more swiftly and more quietly than even the black panther. He can leap higher than the leopard. He can soar through the wind with more speed than the eagle. He can dart through the water more swiftly than the shark. This sixth sense, in addition to his human intelligence and his long experience with wild life, has made him a real wizard of the jungle and has taught him to be a foe of all that is evil and unjust among the jungle-born....

Tanero. Tanero is the son of King Koliak, and a god. He assists his sister Nelvana in fighting against the enemies of the "Eskimos" and all of Canada. He has various godlike abilities, including the power to turn invisible, fly at superspeeds, and control the weather.
First Appearance: Triumph Adventure Comics #1 (Hillborough Studios)

Tangi. Tangi is a Sheena clone. She is helped by Ongah, the gorilla.
First Appearance: Dagar the Desert Hawk #14 (Fox)

Tarantula. Jonathan Law is an author who decides to investigate crime and becomes the dreaded, Spider-like Tarantula. He has no powers but has a web gun.
First Appearance: Star Spangled Comics #1 (DC)

Target. The Target is Niles Reed, a metallurgist who doubles as a spy for the U.S. Army (!). Niles’ brother James is killed by gangsters, so the enraged Niles decides to go after them. He designs a special suit for himself, avenges his brother’s death, and then begins helping the military on the homefront. He is partnered with the Targeteers. The Target has no powers, but he wears an “indestructible metallic fiber suit” which renders him bullet- and grenade-proof. He also has spy skills.
First Appearance: Target Comics #10 (Novelty)

Targeteers. Dave and Tommy Reed are the wisecracking and crime- and evil-fighting sidekicks of the Target. They have no superpowers, but have more than enough attitude.
First Appearance: Target Comics #10 (Novelty)

Taxi Taylor. Taxi Taylor, an ordinary taxi driver, invented the Wonder Car and brought it to the US government to use as a weapon against evil. His offer was refused (the officials laughing at him as they did so), and so he decided to use the car to fight crime--to show the government officials they were wrong, of course. Taxi has no superpowers, but the car...the car has enhanced hearing sensors, can fly via collapsible wings, has a "radio-graph" that picks up & transmits wireless messages, can turn into a submarine, has "contra-magnetic electric rays" that can repel or attract, can generate "gas bubbles which agitate waters and create suction," has collapsible ladders, an automatically-regulated net, and chemical/water jets with which he can fight fires.
First Appearance: Mystic Comics #2 (Timely)

Ted O'Neil. O'Neil is an American fighter pilot and "flying soldier of fortune" who joined the RAF and fought the Wehrmacht.
First Appearance: Prize Comics #1 (Prize)

Ted Parrish. Jakeoster contributes the following:

Ted Parris, the Man with 1000 Faces, was a master of disguise.

Terrific Whatzit. McSnurtle the Turtle, an ordinary anthropomorphic turtle, is the subject of a bet between Prince Highness, the governor and comptroller of all things good on Earth-Animal, and Prince Lowness, the overseer of all things evil. Princes Highness and Lowness are wagering about human corruptibility, and to decide the bet they bestow superpowers on McSnurtle. Fortunately (?) McSnurtle is too lazy to give in to temptation. Prince Highness also gives McSnurtle an "Automatic Conscience," which prods McSnurtle into crimefighting. McSnurtle, a citizen of Zooville, becomes The Terrific Whatzit, foe of anthropomorphic criminals everywhere.
First Appearance: Funny Pages #1 (DC)

Terror. An unnamed amnesiac shows up on the doorstep of one Dr. Storm. Storm has isolated a chemical which causes its subject to take on a skull face and gain superstrength. Storm gives the amnesiac the chemical, but while it's taking effect a gang of thugs try to force Storm to join their group. They rough him up, but then the amnesiac comes to and, angered by what he's seeing, turns into The Terror. He kills the gang and returns to Storm's laboratory, only to see and hear Storm die. The amnesiac then decides to fight against crime and evil.
First Appearance: Mystic Comics #5 (Timely)

Terror Squad. The Terror Squad are a trio of refugees from a German concentration camp in Eastern Europe. They are Chuck Wilson (an American), Stanisofski (a Russian), and Twimbly (a Brit), and all three are expert fighter pilots. After they escape from the concentration camp they go into action behind enemy lines. The story ends with them hooking up with the Russians. They have no superpowers, but are pilots and guerrilla fighters
First Appearance: USA Comics #6 (Timely)

Terry. He is the two fisted, cigarette-smoking, tough guy pal and sidekick of Lucky Coyne.
First Appearance: Dynamic Comics #1 (Dynamic)

Terry Vance. Terry Vance, "the Schoolboy Sleuth," was a boy detective. He had an attic laboratory in which he conducted a number of experiments, and he was successful at inventing useful objects, like his "large gas model airplane with radio control," his ultraviolet flashlight, and his "detectoscope," a "sensitive microphone connected to earphones and operating by two batteries" that can listen through solid stone waalls; Vance may possibly have had superhuman intelligence, so varied were his interests and achievements. He monitored police broadcasts on his radio, and when a case attracted his interest, he swung into action, accompanied by his "able assistant," the monkey "Dr. Watson." Dr. Watson had a very limited vocabulary ("EEEK!" "EEE...EEE...EEE!" "OOK") but was definitely sentient, capable of following Vance's instructions and using his "tiny candid-camera" to help Terry solve crimes. Terry, for his part, was a clever sleuth, known to the police and welcome at crime scenes. Terry was also helped by his older friend, the ace reporter Deadline Dawson.
First Appearance: Marvel Mystery Comics #10 (Timely)

Texas Kid. The Texas Kid is the "Robin Hood of the Range." In his only appearance he was in action against raiders and desperadoes who are burning settlers alive in the land around the Red Rim Canyon in Texas. His horse's name is Spot.
First Appearance: Daring Mystery Comics #1 (Timely)

Tex Thomson. Tex Thomson, a cowboy, strikes it rich in the oil fields of Texas and then leaves it. He has a wide range of exploring adventures until he is asked to watch over a shipment of food on its way to Europe. The liner is sabotaged and sunk, and Tex is the only survivor. He returns to America and begins fighting crime in "Center City" as the costumed, whip-wielding "Mr. America." Later still he goes to fight the Germans in Europe as the Americommando. He is teamed with Bob Daley, later the costumed Fatman. Tex has no powers but is good in a fight.
First Appearance: Action Comics #1 (DC)

Tex Trainor. Tex is a freelance test pilot (usually a cattle puncher) in the American southwest. He's an eccentric, afraid to ride in autos or trains, but quite willing to risk any danger in mid-air. He of course hates the Germans and fights against them and their agents whenever he can.
First Appearance: Air Fighters Comics #1 (Hillman)

Thelma Gordon. Thelma is the girlfriend and sidekick of Bob Dickering, aka the Hangman. Michael Norwitz says, about her, that "Thelma didn't have a costume but she knew his identity and helped him on cases, doing the legwork, as it were (and a nice set of legs, too."
First Appearance: Pep Comics #17 (MLJ)

Thin Man. Bruce Dickson, an explorer, discovered the lost Himalayan city of Kalahia and was given the ability to stretch himself by the inhabitants; he then returned to America to fight crime and evil and that stuff.
First Appearance: Mystic Comics #4 (Timely)

13. Harold Higgins is a very lucky child, up until his fifteenth year, when his parents are murdered. From then on he dedicated himself to capturing murderers, first as a private investigator and then as a costumed superhero. He is assisted by Jinx. He is very, very lucky though it's not clear whether this is an actual superpower or not.
First Appearance: Daredevil Comics #3 (Lev Gleason)

Thor. Grant Farrel, a scientist, is trying to perfect his new electrical conductor when he's struck by a bolt of lightning. (I hate when that happens) He thereby gains the powers of Thor, the god of lightning, and so, naturally, begins fighting crime. Whenever he is in danger lightning strikes him and he gains Thor's abilities of superstrength and lightning projection.
First Appearance: Weird Comics #1 (Fox)

The Three Cheers. "Sis, Boom and Bart were framed by a Nazi agent and were forced to leave the U.S. services. They banded together as the Three Cheers and search for the framer to vindicate themselves."
First Appearance: Our Flag #1 (Ace)

3Xs. The 3Xs are a famous trio of crime-busting brothers with a suspicious similarity to Jack, Doc, and Reggie, the three-man team of the radio show "I Love A Mystery." No origin is given to them. 1X is the Sam Spade-like detective of the brothers; 2X is the bald "walking encyclopedia," and possible inventor (he uses a "disintegration gun"); and 3X is the hulking "strong-arm" of the brothers.
First Appearance: Mystic Comics #1 (Timely)

Thunderer. See Black Avenger.

Thunderhoof. Thunderhoof was the "mighty half-legendary stallion whose brave exploits wrought history in the annals of Old Arizona." These exploits included fighting crime, on behalf of both whites and natives, and in general doing good.
First Appearance: sometime before or during Black Terror #14 (Better Publications).

Tiger Girl. Tiger Girl is a blonde Sheena-style heroine. She is from India who works the mean streets of Africa's jungles, enforcing justice with the help of her whip, her pet tiger Benzali, and her Sikh servant Abdola.
First Appearance: Fight Comics #32 (Fiction House)

Tiger Hart. Saturn, in Tiger Hart's universe, is like Earth during the Middle Ages, and Tiger Hart, "who was dreaded by the lawless," is the horned-hat wearing Thrunk Broadchest hero. He even lived in a castle and used a sword. Except for its location, Saturn, there's nothing science fictional about "Tiger Hart," which makes one wonder what the strip was doing in Planet Comics. But oh well....
First Appearance: Planet Comics #2 (Fiction House)

Tigerman. Tigerman was a "white youth who has been raised by natives, and who rules the jungle with his tamed Bengal tiger, Balu." (And his friend Rangoo, the chimp). Interestingly, Tigerman's features and his adventure made it look as if he was active in the jungles of India, rather than Africa. Tigerman is a Tarzan...imitator...with all of Lord Greystoke's skills.
First Appearance: Daring Mystery Comics #6 (Timely)

Tim. Tim Roland works at the same drugstore as Bob Benton. When Bob discovers a formula that gives him super-powers, he confides his secret in Tim, and so when Bob becomes the Black Terror Tim becomes his sidekick Tim. Tim, who takes the same formula as Bob, has superstrength and limited invulnerability.
First Appearance: Exciting Comics #9 (Better)

Tiny. Tiny is the sidekick of Ragman. He has no powers.
First Appearance: Catman #1 (Holyoke)

TNT. Thomas "Tex" Thomas is a high school chemistry teacher who works on chemistry experiments with his friend and student, Dan Dunbar. They discover that they've been absorbing the chemicals and that when they come into contact with each other they create a big explosion which leaves them charged for a time with superspeed, strength, and invulnerability. They decide to put these powers to use as TNT and Dyna-Mite.
First Appearance: Star-Spangled Comics #7 (DC)

Tomahawk. Tom Hawk was adopted as a boy by a tribe of Indians, who taught him their skills. As an adult, he fights for the Americans in the Revolutionary War, but also takes on evils of all nationalities on the frontier and in the cities of early America.
First Appearance: Star-Spangled Comics #69 (DC)

Tommy the Amazing Kid. Tommy is the sidekick of the Amazing Man. He has the same powers as his mentor: great superstrength, invulnerability, and the ability to "make himself disappear in a cloud of green vapor."
First Appearance: Amazing Man #5 (Centaur)

Tom Kerry. Tom Kerry is a fightin' District Attorney, as willing and able to use guns to solve a crime and cure criminals of what ails them as he is to use the law.
First Appearance: Big Shot #1 (Columbia)

Tommy Tomorrow. In the middle of the 21st century Thomas Tomorrow graduates at the top of his class and joins the Planeteers, a group of solar policemen. Tommy works his way up to become their best agent and one of their leaders, fighting against criminals both alien and human as well as having all sorts of outer space adventures. He is armed with a ray gun and has a powerful single-person ship.
First Appearance: Real Fact Comics #6 (DC)

Tommy Tyme. Tommy Tyme is a typical Brooklynite kid very similar to Brooklyn (of the Boy Commandos) and Scrapper (of the Newsboy Legion), although Tommy was (as far as I know) not done by Joe Simon or Jack Kirby, as Brooklyn and Scrapper were. Tommy, in his first issue, is fishing when he pulls in a genie, who tells Tommy that he's allowed one wish. Tommy is nudged by the genie as to what he hates more than anything. The inevitable answer is of course "School!" so the genie gives Tommy the "Clock of Ages," which--well, Ronald Byrd says it looks like an alarm clock, but my memory says in later issues it looks like a pocket watch--which allows Tommy to travel back in time; he sets when and where he wants to go back, and then the watch's alarm, which will bring him back to the present. Tommy has adventures in various times and places, aiding Merlin and Horatio (of "Horatio on the bridge"), although most of the time his adventures are done so he can correctly answer the questions of his disapproving school teacher. Like Brooklyn, Tommy is good with his fists and a crack shot with a pea-shooter.
First Appearance: Young Allies #7 (Timely)

Tommy Paige. "Tommy Paige, Marine Correspondent, starts out with his combat unit, to cover an invasion story--but Tommy is too much an AMerican to stand idly by while his buddies do the fighting! It isn't long before he shows the Japs what is meant by the 'Power of the Press'--in a manner of speaking, that is!"
First Appearance: Blazing Comics #1 (Enwill Publishing)

Tom Powers. Tom Powers, otherwise known as "Powers of the Press," is the "ace reporter of the Free Press" newspaper.  He fights crime with the help of his sidekick "Candid Kenny Roberts," a photographer.
First Appearance: USA Comics #3 (Timely)

Tom Sherrill. Sherrill is a scout on America's frontier in the days of the Revolutionary War.
First Appearance: Jumbo Comics #1 (Fiction House)

Topper. Barry Graham is the Topper, a top-hat-and-tails wearing member of the upper classes who puts on a domino mask to fight crime.
First Appearance: Samson #6 (Fox)

Tor. Jimmy Slade is a press photographer who has a secret: he’s actually a powerful magician. When someone needs help, or if evil threatens, Jimmy puts on a fake mustache and magician’s costume and flies in to help. He speaks his spells backwards, ala Zatara, and can do whatever the plot calls for him to do.
First Appearance: Smash Comics #14 (Quality)

Tornado Tom. A farmer is picked up by a cyclone and thrown about for hours on end before being deposited back on Earth, without his memory. He gains in exchange superpowers, however, and he uses these to fight crime. He has the speed and strength of a tornado.
First Appearance: Cyclone #1 (Bilbara Publications)

Toro. The Human Torch was flying by a circus one day when he noticed a boy who was fireproof. He approached the boy and the two
teamed up, with the Torch teaching the boy, Toro, how to control his flame. They had a number of adventures together during the Golden
Age, with Toro becoming a member and leader of the Young Allies and later a member of the All-Winners Squad, but in late 1948 Toro
was replaced as the Human Torch's sidekick by Sun Girl.
First Appearance: Human Torch Comics #2 (Timely)

Torpedo Man. Don Wallace puts on a costume which gives him the ability to fly and fights crime. Jakeoster adds, "Torpedo Man's headquarters were located beneath the base of the Statue of Liberty in New York harbor."
First Appearance: Captain Flight Comics #1 (Four Star)

Torro. When Captain Nelson Cole is confronted with a special problem he puts on his magic clothing and whip and becomes Torro, who can fly, is invulnerable to weapons, and is skilled with the whip.
First Appearance: Planet Comics #2 (Fiction House)

Tough Kid Squad. I'm going to turn over the reins of narration for this character to the formidable Ronald Byrd, who describes them so much better than I could:

The Tough Kid Squad (from the one-issue of the same name) consists of Wally and Tom Danger, Butch (the fat kid; evidently his parents expected him to turn out to be the tough kid), Derrick Dawes (the actual tough kid), and Eagle (Timely's first and, mercifully, only Native American kid (think "-um")).  Our main focus is the Danger kids, identical twins, who were orphaned as infants back in 1926, when one Doctor Klutch, business partner of the twins' scientist father Doctor Danger (no relation, one assumes, to the magnet-wielding opponent of Kid Colt; how often do you see just a run-of-the-mill scientist with a name like that?), has the doctor and his wife killed as part of his plan to assume sole ownership of a serum that enhances human development (in 1926? huh).  Separated, the two are adopted by very different men:  Wally is raised by the scholarly Professor Moxon, while Tom falls under the influence of the criminal Wong Chee (the Fox), who calls him "Little Owl" (that whole Asian thing, you know, grasshopper). Both boys, as it happens, received the (well let's just call it a) super-serum before Doctor Danger's death, so that Wally is unusually smart, Tom is unusually strong (and scrappy, so that we have two tough kids on the same team, which seems redundant), and both are quite fit.  Actually, both may have full enhancement, but the fact that Wally was raised by a scientist and Tom by a criminal may have led to the development of each one's given specialty.

Jump ahead fourteen years (or a little more; Tough Kid Squad #1 was published in 1941), when Wally is entering Westcliff School.  At this time, Tom rebels against Wong Chee and sets out on his own.  Naturally enough, the twins meet, and Wally arranges for Tom to enter school as well (They are so identical that Wally takes the entrance exam twice in order for Tom to have a high score.).  They join the football team and become fast friends with Butch, Derrick, and Eagle (Eagle's stereotype aside, it's nice that he was allowed to ATTEND a good school, we've got that, anyway, although he must have been the despair of the grammar department.).  However, the publicity from the game calls the twins to the attention of Dr. Klutch, who still hasn't quite figured out the serum.  I won't insult your intelligence by suggesting that you can't deduce how things proceed from here.

Triple Terror. The Brandon brothers, Richard, Barton, and Bruce, put on costumes and put their abilities to use as Chemix, Lectra, and Menta, the Triple Terror.
First Appearance: Top Top Comics #54 (Dell)

Trojak. Trojak was the son of a Great White Explorer who helped a native African tribe, saving them from an attack by another tribe; the Great White Explorer was killed in battle, and so the unnamed tribe raised Trojak as their own. But because Trojak is white, he has to leave them (even though they make it clear they love him like a son). So Trojak goes a-wandering, helping various tribes (including his own) against bad white men and Germans. Trojak is the "Tiger Man," whose best friend is "Balu, the Tiger" (even though there are no tigers in Africa...but never mind) and "Sator, the falcon;" he can speak to the animals, and has the usual skills of a Tarzan...imitator. Interestingly, the tribe that raised him finds his strength and ability to communicate with animals as exceptional as the reader does; it is not a normal thing to them.
First Appearance: Daring Mystery Comics #2 (Timely)

Trooper "Pat" Corrigan. Corrigan is a two-fisted, gun-wielding state trooper for New York who diligently patrols the highways and by-ways of rural New York state.
First Appearance: Captain Aero #1 (Holyoke)

Tuk. Tuk was a caveboy, similar to DC's Anthro (who, I should point out, came long after Tuk). To quote from the text,

     Ak, the last of the shaggy ones, called him Tuk! But the boy didn't realise that Tuk meant 'Avenger' and that he was destined to
     roam the prehistoric wilds of 50,000 B.C. (sic) in search of Attilan, Island of the Gods, to reclaim a lost throne...!

Tuk actually has a somewhat complicated history. Years ago the the "hairless ones" are abandoned on the shores of an unnamed land. The
"hairless ones" are a tall, handsome, muscular blond man, his sad-faced black-haired wife, and their infant son. They are left on the shores
of the land by other hairless ones, who "departed across the long waters in a log with white wings;" the final words by the blond to his
departing comrades is "Leaving us to the beasts, eh? Well, we'll be back. Do you hear? Kadir will fall!"

The pair are attacked by "Gholla the woolly horned" (some kind of rhinocerous); the blond wrestles and kills Gholla, but the rhino runs the
blond through, and he dies in the arms of his wife. The wife is then attacked by "the four footed killers from the Forest. Kag, the lion-wolf
was first to arrive." Luckily for the woman Ak ("the last of the shaggy ones," presumably meaning he is the last of the Neanderthals) swings
down from the trees to rescue her, and "for many suns to follow" he serves her, "a living goddess." But then one day he is too long
gathering food and she is attacked by "Gru, the lion." Ak kills Gru, but the woman dies from her wounds.

Ak relates all this to Tuk and then tells him that he is the child, now possibly 10 years old, of the "hairless ones." He leaves his "beloved
rock" and goes journeying; he fights off "Goreks! Brain eaters!" and gets his life saved by his new friend, Tanir "the Cro-Magnon." In later
stories Tuk fights the "pre-historic" "hairy ones," the "evil witches of Endor," helps the Princess Eve regain her throne in the city of Atlantis,
and defeats the evil "Bonzo" and his gang of brutes (he kills them).
First Appearance: Captain America Comics #1 (Timely)

Tulpa of Tsang. "In faraway Tibet a few of hte holiest Lamas are said to possess strange mystical powers. By employing an age-old secret of concentration they can actually will unto being Tulpas of phantoms of themselves.  Such a lama was Tsang."
First Appearance: Colossus Comics #1 (Funnies)

2023 Super-Police. Rex, Joan, the Professor and Axel are members of the Super-Police of the year 2023. Their brief is the whole Earth, although they seem to represent the U.S. ("There are 6 billion stories on the lonely planet. This is one of them. My name is Rex. I carry a holo-badge") They fly around the world in the Hi-Lo, a superplane, which receives SOSs on "photolight" and which travels around the Earth by creating a "tubular wall of cosmic rays" and which allows the Hi-Lo to zoom through a vacuum either in the stratosphere or under the seas or even into space. The Hi-Lo is also armed with "cosmic ray guns" and other high-tech weapons and detection instruments. They take on wizard-pirates and other such types. They have no superpowers, however.
First Appearance: New Fun Comics #1 (DC)

Twilight. Sergeant Terry Gardner, a Marine who was a private detective before joining the Corps, tangles with some Germans who mean to kill the man Gardner is bodyguarding. The Germans, though, kill a gypsy, and the gypsy's parrot, Polly, helps Gardner to avenge his owner's death. Polly visits Gardner and gives him a card telling him that "At Twilight you will be Master." Thus inspired Terry makes a costume for himself and begins fighting crime. He is helped by Polly (in some stories Snoopy), who he uses to gather information (and to talk to).
First Appearance: Clue Comics #1 (Hillman)

Twister. A nameless man is picked up by a tornado and left back on Earth, a changed man. He now has the ability to become "a part of the cyclone itself" and to control it. He begins calling himself the Twister and working in Manhattan. In addition to his control over tornados he has superstrength, flight, and can whirl his arms around to create tornados, Flash-style. He also wields the fearsome Cyclone Gun, which blows blasts of air.
First Appearance: Blue Bolt #13 (Funnies, Inc)

Two-Gun Kid. Clay Harder is a singing cowboy who wanders the range, dispensing justice with his six-shooters and his fists.
First Appearance: Two-Gun Kid #1 (Timely)

Ty Gor. "Tyrone Gorman, raised by a tigress in the wilds of Malay, has been brought to America by explorer Davis and his daughter Joan." Predictable wackiness ensues.
First Appearance: Blue Ribbon Comics #4 (Archie)

Typhon. Typhon is a Bronc McThrustTorso type who is an undersea adventurer and pilot/creator of a supersubmarine.
First Appearance: Weird Comics #1 (Fox)

Typhoon Tyson. "Typhoon Tyson, master marine and adventurer, is skipper of the salvage steamer Sea Lion. His Chief Mate and partner is Salty, hard-bitten Anzac Peters." Naturally, their job brings them in the way of adventure.
First Appearance: Banner #3 (Ace Periodicals)

Introduction
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