The Legion of Super-Heroes has been the go-to team to defend the worlds of the 30th and 31st centuries. Combined, they are the most powerful team in DC Comics. Nevertheless, sometimes they need a little extra strength. So, they use their time-traveling abilities to pull others into their century.

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Conversely, there are some Legionnaires who were transported to the present and decided to stay for a spell. While they eventually returned to the future, they made an impact in the 20th and 21st centuries.

10 Future to Present: Star Boy

A long-time member of the first Legion incarnation, Thom Kallor was able to change the mass of objects as Starboy. When he traveled to the 20th century, Thom was a patient in a mental hospital. Without medicine from the future, the hero began to re-experience a dual personality.

This condition caused him to forget the reason why he was in the present. To bide his time, he joined the Justice Society of America as Starman. During this period, he was an important participant in the restoration of Wally West and his family to the current timeline. Though his true reason for being there was to restore Connor Kent's life, that didn't happen until later.

9 Present to Future: Jon Kent

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Being the pre-teen son to Clark Kent and Lois Lane was a challenge at first. Especially when his family had to hide out as another Superman saved people. Once his father returned to his original costume, Jon appeared with him several times. Then, his grandfather, Jor-El, took him on an outer space vacation.

He returned as a 17-year-old. Ironically, it was a perfect age to join the Legion, which he ended up doing when he helped create the 21st-century version of the United States. Hence, the reason the entire Legion showed up in the present to take him to the 31st century.

8 Future to Present: Phantom Girl

You can blame Legionnaire Mon-El for this one. In the "Five Years Later" storyline, the Daxamite seems to kill the Time Trapper. The result is a new timeline where Mordu was a galactic emperor and the Legion didn't exist.

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Enter honorary Legionnaire Ron Vidar. Using information stolen from Mordu's mind, he rebuilds the original timeline. To do so, he and one of Mordu's wives, Glorith, need to bring someone from the 20th century to the 30th, and vice-versa. Hence, the reason Phantom Girl was chosen. Eventually, she ended up a member of L.E.G.I.O.N.

7 Present to Future: Mon-El

Mon-El's story is one of pain and sadness. Like Superman, the hero gained his powers via the rays of a yellow sun. Unlike the Man of Steel, Mon-El's weakness was not kryptonite. It was lead -- a plentiful element on Earth and other planets.

Without the necessary treatments to help him, Superman had no choice but to place him in the Phantom Zone. He remained there for 1,000 years, until he was discovered by the Legion. By then, a vaccine was ready to help the young hero. A grateful Mon-El agreed to join the Legion shortly after that.

6 Future to Present: Timber Wolf

Another change that took place in the "Five Years Later" Legion of Super-Heroes was Brin Londo's continued transformations. In the years between the previous and current Legion series, Timber Wolf was exposed to something that transformed him into a creature his friends called Furball. The illness was stripped away by Darkseid, leaving Brin to slowly die.

Someone else affected by Darkseid, Aria, came to Brin's bedside. As a result, not only did she transform him into a human/wolf hybrid, she brought them to the 20th century. The pair remained there for several months before they both returned to the future, with Brin remaining in the same form.

5 Present to Future: Supergirl

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Two versions of Supergirl visited the future. In the 1960s, she was an official member of the Legion along with her cousin Superboy. This was a bit confusing to both them as the Boy of Steel and Maid of Steel came from different years in the 20th century.

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Decades later, a post-Crisis Supergirl made her way back to the 3000s. However, it wasn't with the original version of the Legion -- it was the group known as the Threeboot team. This Supergirl helped raise their morale during a down period. Also, she was instrumental in leading the search for a missing Cosmic Boy.

4 Future to Present: Karate Kid

Val Armorr was the first Legionnaire to have his own series. Instead of being an event-based mini-series, Karate Kid lasted 15 issues between 1976 and 1978.

The premise of the comic wasn't typical of other books. Val travels to the 20th century to prove his worthiness to the father of the woman he loves, Princess Projectra of Orando. Along the way, he encounters heroes like Robin and criminals such as Major Disaster and the Lord of Time. Decades later, Val returned to the 21st century disguised as the villain Trident. Turns out, he was there to help return Wally West to the present.

3 Present to Future: R.J. Brande

If you recall, Phantom Girl was sent to the 20th century in exchange for someone who would travel to the 30th. A person who would be an important figure in the Legion's founding. In this case, it was R.J. Brande, the man the original members saved from terrorists.

Except, it wasn't Brande at first. It was an unnamed Durlan who was a friend to L.E.G.I.O.N. leader Vril Dox II. Since Durlans weren't welcome on Earth in the 30th century, he became R.J. Brande. His sizable wealth helped finance the Legion for many years.

2 Future to Present: Founding Members

Cosmic Boy, Saturn Girl, and Lightning Lad have visited the 20th and 21st centuries numerous times over the decades. However, it's their first appearance that's the most important. They spent several days in Smallville to find a certain Boy of Steel.

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Since then, the Legion's founding members have returned to the present several times. In the post-Crisis world, Cosmic Boy and his girlfriend Night Girl traveled to the 20th century for a vacation. Recently, Saturn Girl was a prominent player in both Rebirth and Doomsday Clock. 

1 Present to Future: Superboy (Clark Kent)

Chameleon Boy, Saturn Girl, Superboy, Lightning Lad, and Cosmic Boy stand together

It had to start somewhere. For Superboy, it was Adventure Comics #247. This is when the young Clark Kent met the Legion's founding members, As a result, they brought him to the 30th century.

In the 1960s and 1970s, Superboy would travel to the 30th century for numerous adventures. Even when he resigned he still visited the future to see how his favorite teens were doing. Thanks to his visits, a legacy was born.

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