- "How many Wells are we talking about here?"
- "How many universes were there in the multiverse?"
- —Eobard Thawne (impersonating Harrison Nash Wells) and Caitlin Snow[src]
The mind of Harrison Nash Wells is the place where all the doppelgängers of Harrison Wells ended up after the Anti-Monitor Crisis. All its residents were later transferred to the fusion sphere to power the Artificial Speed Force after Nash's sacrifice.
- "I've been seeing a lot of Wells lately. I mean, up here. A lot. I don't know how many there are, but the wizard Wells, annoying, French Wells, New York City Wells, actually he's alright. And then, Harry Wells."
- —Eobard Thawne (impersonating Harrison Nash Wells) to Team Flash[src]
After the Anti-Monitor Crisis destroyed all Earths, all Harrison Wellses of the original multiverse were folded on each other and their brainwaves were tangled with Harrison Nash Wells, the last surviving Wells. Not long after Crisis, Nash saw illusions of Harry Wells of Earth-2, Harrison Sherloque Wells of Earth-221, Wells the Grey of Earth-13 and a Wells from New York City from an unidentified Earth. As Eobard Thawne's body was a direct copy of the Earth-1 Harrison Wells, his brainwaves were also transferred to Nash's mind. H.R. Wells of Earth-19 would also be transferred to Nash Wells' mind despite having died long before the Crisis occurred.
The mind of Harrison Nash Wells is a cave on Earth-13 which is the location of Maya's death. When Eobard Thawne was about to take over his mind and body, Barry Allen, Cisco Ramon, and Cecile Horton ventured into his mind to stop him. Cisco persuaded Nash to face that memory and it banished Thawne away as negative tachyons.
During the construction of the artificial Speed Force machine, the energy source became an issue. After Barry took Chester away for a coffee, visions of Harry Wells, Sherloque Wells, H.R. Wells, and Harrison Orson Wells appeared to discuss their solution. Nash claimed Harrison Orson Wells to be a new one he hadn't encountered. The solution required transferring all the multiversal particles from all the Wellses inside Nash to the fusion sphere, at the cost of Nash's life due to the volatility of the particles requiring an organic receptor. Nash would refer to his doppelgängers as "bozos" for suggesting it and stormed off, refusing to sacrifice himself.
Nash Wells would later try to transfer all the particles without touching the fusion sphere with the help of Allegra Garcia, Barry, and Chester. However, the volatility of the multiversal particles caused Barry to push Allegra out of the way, transferring all the Wellses into Barry's mind. Sherloque, H.R., and Wells the Grey would take over Barry's mind till it became apparent that the particles were killing him. Allegra would assist pushing all the Wells particles back inside Nash.
Nash would realize that the only quick solution to getting Barry's powers back was to sacrifice himself to the artificial Speed Force. As the transfer commenced, H.R., Sherloque, and Harry would reemerge to say their goodbyes to Team Flash. All the Wellses, including Nash, were transferred to the fusion sphere, powering the artificial Speed Force and granting Barry his powers back.
However, it turned out that all the particles of the all the Wellses except for 0.01% were transferred to the fusion sphere to power the artificial Speed Force. Those 0.01% of the particles resurrected the Earth-Prime Harrison Wells, effectively removing Wells from the timeline after his original death in 2000. The particles left an imprint of memories from multiple Wells doppelgängers. Wells would theorize it was a way to balance the timeline due to the removal of all the other Wellses from the timeline.
- Eobard Thawne ("exorcised" as negative tachyons)
- Harrison Wells (deceased)
Nash sees the illusion of Harrison Wells
- The only way to travel into Nash's mind is through the use of MAD 2.0.
- Even though others can travel into Nash's mind, they could not communicate with its residents.