Remember the big Ash x Serena scene in the preview where Serena manages to find Ash? Well, here's how it turned out.
When I said that something bad was going to happen, this was
exactly what I had in mind. I called it!
For those who are wondering what's going on here, Ash apologizes to Serena for leaving so suddenly. Serena tells him that if there's anything wrong, he should talk to her, but Ash states he doesn't want to talk right now. Serena explains that she understands his pain by recounting how she just her first Pokemon Performance, but Ash lashes out and says she doesn't understand. Serena still encourages to have a conversation, but Ash still doesn't want to talk. She then throws a snowball at him, know visibly crying at this point, and says that Ash she knows is always optimistic and never gives up until the very end. She throws more snowballs at him, and then she says,
"You're not the Ash I know!" She runs off, and Ash says,
"Am I... not myself."
Amourshipping haters will probably look at this scene and think
"This argument killed Amourshipping," but the one thing to keep in mind is that
part of true love always involves arguments, so if anything, an argument can make a bond even stronger than before. Heck, when the snowstorm kicks in, Serena decides to help Ash and you can see she is still worried about him throughout the episode. By the end episode when Ash and the group reunite, Ash thanks Serena for getting mad at him because it helped him figure things out. Serena is visibly happy following that.
This episode even shows more of Ash's childhood far more than any other Pokemon series.
Again, no subs, but it's pretty easy to make out what's going on here. This side of Ash's childhood is even a nice parallel to Jack Walker's backstory in the Manaphy movie (Jack Walker was that Pokemon Ranger for those who forgot who he was). Another nice detail is that the five Pokemon Ash is with in the cave represents each generation of Pokemon minus generation 5 (Oddish = Generation 1, Sentret=Generation 2, Zigzagoon = Generation 3, Budew = Generation 4, Scatterbug = Generation 6). All of the Pokemon in the flashback are also generation 1 Pokemon, and when I saw the Caterpie, I was reminded of the Caterpie Ash caught (like, although very doubtful, the Caterpie later recognized Ash). Definitely a touching scene overall; it even gives context to why Ash loves Pokemon so much.
Team Rocket also wasn't annoying for once when they appeared. They try to capture Ash's Pikachu when they find it all alone, but they decide to give up on doing so when they realize Pikachu's Thunderbolts are not as strong as it normally is because he is still feeling down about Ash's absence. When they appear again after Ash returns, they feel pretty happy that Pikachu is back to his normal self with the powerful Thunderbolt attacks.
They even show Greninja's side of the issue. It escapes its Pokemon Center bed to search for Ash, and there's even a moment when it contemplates about it's recent losses. Puni-chan even manages to help it out by transforming into its 10% Forme, finding Ash through the nearby Zygarde cells, and telling Greninja about Ash's location.
There's even a pretty sweet scene where the Spewpas that Ash saves evolve into Vivillions and fly into the night sky after the snowstorm. I was reminded me of the episode when Ash released his Butterfree when I watched this scene. Heck, I think there's some deep symbolism. The Spewpas evolving into Vivillions and the flying off symbolizes how Ash and Greninja's relationship finally "evolved" and now it will go off into greater things to come (shocking that the Pokemon anime has been using some interesting symbolism; other examples of symbolism can be found in the Mega Evolution Act IV special and Pokemon XY&Z episode 8 to my knowledge).