Pokemon Sun and Moon's anime series is winding down the final moments of its Alola League arc, and while it seemed like Ash would be bringing it all to an end with his current team he might be getting a new addition to cap everything off. Before everything starts over once more with the introduction of Sword and Shield's Galar region to the anime, it seems that the next episode of the series is teasing a new addition to Ash's team: Melmetal.
Meltan was already a curious addition to Ash's Pokemon roster this season, but the preview for Episode 138 teases that Meltan will be evolving into its much bulkier form with the help of several other Meltan's. As for why they're gathering together remains to be seen.
ポケットモンスター サン&ムーンSeptember 1, 2019
The preview for Episode 138 sees Ash and his friends gather for what looks like the final moments before the final match of the Alola League. It's here that a mass of Meltan's suddenly gather and dance around before forming together. While the resulting glowing mass doesn't look like Melmetal just yet, there's a brief moment where its silhouette can be seen just slightly.
The reason behind Melmetal's reveal is left up in the air as the Meltan might be forming together in order to help Ash in his final match. Or it could just be the Meltan up to their various shenanigans once more like in previous episodes. But if Melmetal does join Ash's party, this will be a big boost for what could end up being his final Pokemon League run. If you haven't kept up with the current run of the anime, the much anticipated Alola League arc is almost at an end!
Pokemon the Series: Sun and Moon is described as such, "What starts as a summer vacation in the tropical Alola region turns into the next exciting chapter in Ash Ketchum's quest to become a Pokémon Master! There's plenty for Ash and Pikachu to explore in this sunny new region, with exciting new Pokémon to discover and interesting people to learn from along the way—including the cool Professor Kukui and the fun-loving Samson Oak.
More new faces will help guide Ash's Alolan adventure, in the form of a group of skilled Trainers—Kiawe, Lana, Mallow, and Sophocles—and a mysterious research assistant called Lillie. Frequent foes Team Rocket have also made the trip to Alola, looking to swipe some high-powered new Pokémon. But they have some heavy competition on the villainy front: the ruffians of Team Skull, who delight in causing chaos and may have more sinister intentions..."