Harrison Nash Wells

"Look, there's no such thing as mystical mumbo jumbo or gods. What there are, are meta-humans, aliens and false gods worshiped by simple-minded people that find comfort in myths. I dispel those myths."

- Nash to Cisco Ramon

Dr. Harrison Nash Wells is an alternate version of Harrison Wells from an unknown Earth. He is a geologist and a myth-buster. Nash is in pursuit of The Monitor because he believes the Monitor's words of the upcoming Crisis are false tales intended to spread fear and Nash's intention is to stop the Monitor's so-called reign of terror.

Early life
At some point before 2019, Nash either learned about or met the Council of Wells. However, he considered them to be idiots.

Arriving on Earth-1
In 2019, Nash traveled to Earth-1 in search of eternium. He broke into McCulloch Technologies in search of it. The following day, he was met by Iris West-Allen and Cisco Ramon, who'd tracked him down. He quickly confronted Cisco, but upon detecting eternium around Iris, approached her. She promptly tasered him, and they took him back to The Central City Citizen office. He eventually awoke, explaining that he was searching for eternium particles, which he had picked up on Iris. Cisco attempted to befriend Nash by implicitly referencing how he and Harry Wells had a rough start before becoming friends, but Nash rejected this and swiftly deployed a smoke bomb. After their confrontation, Nash located some eternium particles in a manhole.

While Barry and Cisco were talking about saving Ramsey's live at S.T.A.R Labs, Nash arrived, revealing his knowledge about Barry being the Flash which he discovered after he put a chip on Cisco. He told them that he could help them save Ramsey if they help him. He led them to steal a cure stored in McCulloch Technologies. When Barry and Cisco got trapped by the security guards, Nash used a device that made them faint for a while. The device was not in the fridge it was supposed to be and they failed to find it. When the guards were coming, Nash used a device to teleport them to S.T.A.R. Labs. Since he still collaborated him, Nash demanded that they helped him with the device he requested. Upon receiving the device from Cisco, he located an underground place where Mar Novu was hiding and intended to open it.

While he tried to do so, however, he was confronted by Joe West. Revealing that he had been watching Nash closely, Joe demanded to know what his intentions were, but Nash refused to elaborate and attempted to attack him, only to accidentally trigger his gauntlet in the process and cause a cave-in. With no way of escape and their air supply rapidly depleting, Nash eventually concocted a plan to blast their way out, although Joe warned against it, as it would kill them, and instead instructed Nash to wait for Team Flash's help, causing Nash to become frustrated of Joe's unrealistic optimism and question Joe's firm faith in his allies, causing Joe to break down as he then revealed Barry's fate to die in the Crisis of 2019, as told to Team Flash by The Monitor, and he has to be faithful as to not make Barry's sacrifice be in vain. Nash was left shocked that Team Flash had met the Monitor and tried to reach out to the now mourning Joe to identify whether the being he described truly was Mar Novu. Just as he was about to activate his gauntlet to reveal he saw the Monitor, Ralph Dibny arrived to rescue Joe and Nash.

As the two recuperated in S.T.A.R. Labs, Nash still refused to explain his intentions. However, after Team Flash offered their help, Nash relented and instructed them to meet him at the tunnels the next morning, claiming that he knew how to save Barry.

When the team came to the tunnels, with Nash having waited there, he claimed that the Monitor was a false god who spread fears through the Multiverse and that he intended to stop his reign of terror. To do so, he told the team that he must go through the rocky walls that he stated contained a portal to The Monitor's realm. However, Nash revealed soon after that they had no means of breaching the eternium defenses that the Monitor had placed on the wall as Barry's did not work and Ralph using a jackhammer on the wall would only cause the eternium to unleash a catastrophic molecular blast that could wipe out all life on Earth-1. He then revealed that the only way to get through was by illuminating the wall using an artifact that could emit UV rays to reveal the eternium and identify which sections he couldn't strike. Later, at  The Central City Citizen office, Nash searched for the artifact that he had detected earlier that could emit UV rays. He met Allegra Garcia who recognizes him as Harrison Wells but he told her that he was Nash Wells. He then realized that the artifact he had detected earlier was Allegra, making him aware that she was a meta-human who could emit UV rays. Nash made a deal with Allegra in which he would reveal everything about doppelgängers, the multiverse, and potentially the end of all life in exchange that she uses her power to reveal where the eternium was located in the Monitor's wall. In the sewers, while talking with Allegra, Nash revealed that Barry Allen was the Flash which surprised Allegra since he is her boss' husband. When Allegra failed to use her powers, Nash later encouraged her by telling her that using powers didn't make her like her cousin. Allegra succeeded and gave Nash enough time to take a picture of the Monitor's code. Later, at The Central City Citizen office, Nash gave a drink to Allegra who was tired after using her powers and Nash left after revealing to her that he was nice to her because she reminded him of someone.

Later on, Nash successfully broke through the eternium wall and prepared to solve the code that would open the portal to The Monitor's realm, satisfied that his chase of the Monitor through the multiverse had come to an end. He commented that he'd traveled across the multiverse for many years to kill the Monitor, who had saved his life under unknown circumstances. Nash heard a voice, presumably the Monitor's, telling him to "submit and begin [his] life anew." Nash asked the voice to show him, but heard that the knowledge was within him. As the symbols on the door glowed, he pushed them in a specific order, causing the door to open. A glowing light came out of the door and sucked Nash inside, with the door shutting once more after he passed through.

Personality
"You selfishly don't believe in anything or anybody."

- Joe West to Nash

Nash is a very aggressive, argumentative person always lost in his goal instead of personal relationships. He is also a staunch atheist, believing not in the supernatural, but being more scientifically minded like his Earth-1 and Earth-2 counterparts. He also shows a very adventurous persona.

Like Harry at first, Nash doesn't seem to have a very high opinion of some of his own multiversal counterparts, considering the Council of Wells, a group comprised of his smartest doppelgangers, to be idiots.

Abilities
"This is what I do. I don't just solve mysteries, I bust myths. I bust them wide open."

- Nash


 * High-level intellect/Expert scientist: Nash, like many of his predecessors, is an exceptional scientist, more specifically a geologist, with him claiming to have performed many scientific miracles. He dismissed the members of the Council of Wells as "idiots," despite their members consisting of some of the brightest minds in all the multiverse, indicating a likely high level of intellect in his assuredness. He also dismissed Cisco Ramon's engineering workmanship as "shoddy" and "subpar." The highly intelligent Joe West noted him for being observant, and he later demonstrated his intuitiveness when he deduced why Allegra Garcia did not like using her meta-human powers. He can quickly perform calculations in his head, such as how much time he and West had left to breathe after a fire depleted the majority of the oxygen in the tunnel they were trapped in, or calculate the location of an inter-dimensional portal leading to Mar Novu's realm. Nash also has a vast amount of knowledge on the multiverse and doppelgängers.
 * Skilled tracker: Nash has been tracking Mar Novu for some time with some success.
 * Master of stealth/Escape artist: Nash can follow his targets for long periods of time unnoticed, and quickly disappear from sight even in broad daylight, he is also skilled in using pyrotechnics to create various subtle explosions and smokescreens to mask his escape, as seen in his both confrontation with Iris West-Allen and Cisco Ramon.
 * Acrobatics/Free-running: Nash was able to scale S.T.A.R. Labs' balcony.
 * Honed senses: Nash sensed Joe West approaching him from behind.

Equipment

 * Tracking device: Nash wears a tracking device on his wrist, which he uses to detect eternium particles. He also used it to detect UV rays.
 * Smoke bomb: He used a smoke bomb to escape from Iris West-Allen and Cisco Ramon. Those bombs were revealed to also work to teleport people, as shown when Cisco and Barry were stealing the cure from McCulloch Technologies.
 * Zip line: Nash used a zipline attached to a grappling hook when preparing to attack Cisco Ramon.