Even for mythical Pokemon, Meltan is pretty unique. Debuting in the franchise as part of a crossover between Pokemon GO and Pokemon Let's Go Pikachu and Let's Go Eevee, Meltan is the first mythical Pokemon capable of evolving. While some may have thought Meltan's time in the spotlight would pass after Pokemon Let's Go Pikachu and Let's Go Eevee, it appears that's not the case, and the steel-type Pokemon may very well have a significant role to play in the upcoming Pokemon Sword and Shield.
According to a 4chan post that was made before Pokemon Sword and Shield were officially announced, Meltan will "tie into" Armored Evolutions and "Legendary lore." Unfortunately, the leaker didn't go into specifics. However, if we believe the rumor that Pokemon Sword and Shield will be introducing Armored Evolutions, it's possible that players will need to have Meltan in their group to trigger them, or something along those lines.
At this point, we don't even know if Armored Evolutions are real or if they were just made up in the 4chan post. And while we would usually write off a random 4chan post claiming to leak video game news as nothing more than someone making things up on the Internet, this one does have a bit more credibility than most.
That's because at least two of the claims in the initial 4chan post have already been confirmed. The post claimed that the games would be called Pokemon Sword and Shield (which turned out to be true), and that their setting would be based on Great Britain. And as we've come to find out, Pokemon Sword and Shield's Galar region does indeed appear to be based on Great Britain.
As for the legendary Pokemon, it's easy to see how Meltan could play a role with at least one of them. One of the legendary Pokemon in Pokemon Sword and Shield is said to be a metal snake, and since Meltan is a steel-type Pokemon, it wouldn't be a stretch for them to have some sort of lore-based connection.
Before fans read too much into this leak, though, we should caution that the information should be taken with a grain of salt. It's quite possible that the rest of the leak is inaccurate, so Pokemon Sword and Shield fans should hang tight for Nintendo to share more information in an official capacity.
Pokemon Sword and Shield will launch later in 2019, exclusively for the Nintendo Switch.