Dimensional Traveler: Implied to be this because of the partner's post credits wish, in that he wished for the player character to be able to freely travel between the human and Pokémon worlds at will.
Heroic Resolve: In the final battle, they manage to muster up the strength to break through the Bittercold's defenses after the positive feelings of the Pokemon in the world fail to weaken it. It's also impossible to actually lose because of it, as they'll just keep getting back up whenever they run out of HP and won't lose any progress in the fight.
Honour Before Reason: In spite of being the only one who can stop The Bittercold from destroying all life, he/she decides to take a detour to save the partner from Munna and the others, even though it's clearly a trap and might even be a bluff.
Last Of Their Kind/Sole Survivor: You're revealed to be this when you learn that all of the mysterious lights you see in the distance are the fallen reminisce of the other heroes that were sent to the Pokemon World to stop the Bittercold and were defeated by Kyurem.
The Quiet One: Unlike the protagonists of previous installments, this one is shown speaking regularly to the other characters throughout the story on occasion (outside of their Inner Monologue).
Retgone: An undeniable law of nature, and what was supposed to happen after leaving the Pokémon world. The members of Post Town and Paradise weren't having any of it.
One of five Pokemon who end up meeting the hero shortly after their arrival in the Pokemon world and do their best to help them from that point on.
Meaningful Rename: The way they instantly take to the nickname you gave them helps reinforce how quickly you're bonding.
Heroic Resolve: In the finale, they manage to defeat Kyurem and make it all the way to the Bittercold before they finally collapse due to the suffocation the latter induces in Pokemon. Even then, they manage to remain conscious through the entire final battle in order to provide the hero with moral support. A great contrast from their first visit to the Glacier Palace, where they end up passing out before they even get close enough to see the Bittercold.
Stepford Smiler: After the player character disappears, they becomes this. Until Hydreigon discovers a way to bring them back.
I Want My Beloved to Be Happy: Platonic version. Despite being hit hardest by the loss, he's the only one hesitant to bring the player back in the post credits, since he knows they must have human friends and family too, and might not be able to see them again.
Not Drawn to Scale: Like many others of his species in...nearly every form of media Pokemon has ever been in, Dunsparce isn't shown at his species' actual height of 4'11" (1.5 m). Please note this is the same size as Salamence. In this game, even Pikachu, who clocks in at a 1'04" (0.4 m) is taller than Dunsparce.
Unless you think that its height could be referring to its length instead of how tall it is, which is how some snake Pokemon, including Dunsparce, are measured here.
Jerkass Has a Point: He's called out for his reluctance to accept Virizion as part of your team, but after she broke his best friend Dunsparce's heart by rejecting his advances to be her friend, his anger is understandable.
Official Couple: With Virizion at the end of the game, despite not liking her at first.
Tsundere: A male type A. This is especially noticeable after he ends up with Virizion in the flying Glacier Palace.
A world famous adventure (in)famous for capturing the hearts of everyone in Post Town, but never returning their feelings. Although normally proud and easygoing, she becomes unusually bitter whenever the topic of friendship comes up. This changes when she meets the Player and Partner.
Badass: She is a legendary and joins your team early on, where she outlevels the team by quite a bit. She also doesn't lose any usefulness either.
Cry Cute: Here and there. The waterworks really kick off after Keldeo apologizes on the Palace.
The First Cut Is the Deepest: The reason she's so distrusting of others is her first friend, Keldeo, supposedly abandoned her to go to the Great Glacier, and later sent a letter claiming he always hated her and just needed an excuse to get away. Since then she never truly trusted any Pokemon, or made any friends.
Nice Girl: Despite being one of the Pokemon with the best reasons to go to the Glacier Palace, she volunteers to stay behind so Dunsparce could go. She is also the first one to accept the player's claims of being human without hesitation while the other Post Town members had doubts or were too shocked.
Official Couple: With Emolga at the end of the game, despite the fact he was the only Pokémon who wasn't head over heels for her.
First Episode Spoiler: His part of the plotline takes place in just the first few hours of the game, yet that part is full of spoilers and it's difficult to talk about him without encountering a spoiler.
Freudian Excuse: After Gurdurr's injury, someone toyed with all three carpenters by asking them to build a house, and then destroying it in front of them and mocking them just for the lulz. From that point on, Gurdurr has been a scam artist until the partner persistantly asks to build him a house.
Heartbroken Badass: Despite being permanently injured, he still holds out pretty well both as a carpenter and as a fighter.
Start of Darkness: Though he was considered a great craftsman once, an accident left him scarred and unable to complete work up to his past standard. As a result, his career faltered. Throw in a malicious prank a certain Pokémon pulled that destroyed what remained of his confidence, and...
A mysterious character who bumps into the partner in Post Town one day. He's a criminal who helps out Gurdurr in his attempts to scam the player. After this, he is dragged back to Post Town by Quagsire and forced to run the Move Shop.
Crash into Hello: The first time he's seen, he plows right through the player character. And steals the gems the player character spent the last dungeon collecting.
Even Evil Has Standards: When Gurdurr tells him he sent the heroes to gather more gems, he seems shocked by how he's going to keep stringing them along indefinitely. However, when Gurdurr calls him on this, he immediately stops shedding tears, subverting it.
Jerk with a Heart of Gold: Despite all appearances to the contrary, he really is happy when the player returns to the Pokémon world.
Sour Supporter: After being forced to help you by Quagsire. He warms up eventually.
The owner of the land the partner purchases, who quickly becomes a fixture in Paradise as he oversees your decisions of which recruits you take out on missions. He turns out to have once led a firm that punished criminals.
Broken Ace: Became famous for his efforts punishing criminals. At the beginning of the game, he resides in a barren desert and is extremely apathetic towards everything.
Not So Stoic: After the partner takes a request for less money simply because the Pokémon needs the most help, Quagsire starts trembling uncontrollably and compliments the partner.
Retired Badass: Once led an organization that punished criminals and became widely feared among criminals.
Verbal Tic: Quagsire, hmmm, hums quite a lot any time he speaks.
Dissonant Serenity: She almost never loses her cool, even if the topic in question is about the world ending.
Nice Girl: Whatever happens, she's always gracious and kind.
Only Sane Mon: She's the only member of Post Town who doesn't immediately lose her head when the partner announces the end of the world. She is also one of the few to berate the other citizens over losing it and giving up hope in the player.
Supreme Chef: Hydreigon seems to hold her cooking skills in high regard.
A Pokemon that sets up shop at the start of the V-Wave season. He likes to go on about his V-Wheel.
Bunny-Ears Lawyer: Assuming he created his V-Wheel, he must be a brilliant Pokémon. On the other hand, he is very quirky, hammy, and loves to go on his V-Wheel.
Virizion's former best friend. Claims to have gone to Great Glacier just to get away from her, and that they never really were friends to begin with. He's lying. The real reason he said this to her was because he accidentally stumbled upon the Big Bad's plot, and didn't want to put her in danger as a result.
Break Her Heart To Save Her: Keldeo does this to Virizion prior to the events of the game, having discovered the Bittercold and thus ended up being chased by Kyurem and his underlings. Not wanting to risk Virizion sharing his fate, he hastily wrote a letter saying that he never liked her and only pretended to go to the Glacier Palace in order to get away from her. While it kept her from going there (for a while, anyways), having someone she considered her best friend say that also caused her to become very cold and distrusting of others as a result.
Gadgeteer Genius: He picked up the skill of using Entercards in his travels and got good enough at it to make Umbreon and Espeon, who devoted their lives to researching dungeons, completely amazed. Hell, he made Entercards that could travel through the sky. Espeon, understandably, is very impressed and jealous.
Honor Before Reason: He's imprisoned in the Glacier Palace, but not because Munna and co wanted him out of the way. He went back after they let him go, because he thought he could convince them that the world was worth saving. He was wrong.
A Dragon/Dark Pokemon who's first seen terrorizing a Munna. Revealed to be very important in the late game, to the point of being essentially a Walking Spoiler.
Awesome, but Impractical: Sure, he is a level 64 behemoth that can one, or even two-shot, any of the foes encountered during his stint as a guest party member. Unfortunately, a good portion of these dungeons have Lilligant, who can make him dangerous to you if they set off Teeter Dance.
Badass: Saves you twice from Munna's goons, dukes it out with a Salamence, and joins you temporarily as a (rather overpowered) guest character.
Big Eater: A given for his species. He becomes a regular at Swanna's cafe in the post-game, and has a bad habit of driving up the bill for whoever decides to accompany him. He's responsible enough to pay off his share sooner or later, though.
Big Good: Turns out he's the one who took the initiative in saving the world by calling humans into it once he realized that no Pokémon could stand against the Bittercold.
Crutch Character: Actually joins your party for a bit during the story... at level 64! When you're likely to be in the late 20's. Unfortunately, this is where he accompanies you on dungeons.
Dark Is Not Evil: Easily one of the nicest characters in the game, despite his rather unsettling appearance.
Expy: Seemingly evil Pokémon who is thought to be destroying the planet but is actually good and trying to save it. Sound anything like Grovyle from Explorers of Time/Darkness/Sky?
Gaia's Vengeance: A rare heroic example. Hydreigon isn't a true Pokémon, but rather a form taken by the Voice of Life, a being who embodies the world's will to survive and acts as one of its sworn protectors. He chooses to identify himself as the species of Pokémon he appears to be, though.
He later goes on to note that there are actually multiple Voices of Life who reside in other regions of the world, though none of them are actually seen.
Immortality: However, he returns no worse for wear in the ending, cheerily explaining that his existence is tied to that of the world, and that he'll live as long as it does. It apparently just takes a while for him to manifest his physical form again if it's destroyed.
Evil Cannot Comprehend Good: Genuinely cannot understand why the team wants to save the world given how bleak and hopeless it has become.
Evil Counterpart: To the player. Both the player and Munna found themselves in a situation where they had nothing and no-one to help them, and were then taken in and accepted by strangers. In the player's case, it was the partner, who helped them become a force for good. In Munna's case, it was the rest of Kyurem's minions (i.e. Toxicroak, Gigalith, Purugly, Salamence, Excadrill, and Chandelure) who all allied themselves with Kyurem and decided to help ensure the world's destruction.
Also to Virizion, who ended up going on a quest to save the world after she thought her best friend Keldeo abandoned her, Munna instead goes on a quest with her friends to destroy the world because she thinks it's the best idea for herself and her friends.
Establishing Character Moment: In his second appearance, he comes out of nowhere, kills Hydreigon, beats you to a pulp, and then threatens to finish you off unless you stop "interfering in the world's fate".
Expy: Of Dusknoir. A powerful Pokémon who is initially helpful, but eventually becomes an enemy and is fought before the final boss in order to protect the future as they recognize it.
The Fatalist: Partially because he can actually see into the future.
Graceful Loser: Offers the player honest advice after his defeat, and saved everyone from being killed during the Glacier Palace's collapse.
The Heavy: The Bittercold is never seen before the final boss fight (and it's ambiguous whether it can even leave its Eldritch Location), so Kyurem and his minions provide the game with a visible antagonistic group to pit the heroes against.
Hero Killer: A G-rated variation of this considering that all of the mysterious lights you see in the distance are the fallen reminisce of the other heroes that were sent to the Pokémon World to stop the Bittercold and were defeated by Kyurem.
Knight of Cerebus: The mood of the game gets much darker after he decides to take some action of his own to secure the world's future, showing off his villainous side in the process.
No-Nonsense Nemesis: When he confronts the party in Scorching Desert, he immediately proceeds to subject Hydreigon to a case of Literally Shattered Lives, then beats the hero senseless without uttering so much as a word beforehand. Ends up being subverted when he heeds the partner's pleas for mercy instead of finishing off the hero like he had initially intended to, though not without threatening to destroy both of them if they continue to try to change the world's fate.
Could also be seen as an Expy of Nyx. Both were brought about through the negative emotions of the beings living in their worlds, and their only goal is to being about The End of the World as We Know It. Though granted, Nyx itself doesn't want to bring about the end of the world. The Bittercold, however...
Zeromus is also fair game for expy-age here. Both are defeated through basically everyone helping the heroes from afar, and they cannot be damaged until a certain point in the battle. To be fair, that also touches back on the aforementioned Giygas references (sans the fact that he could technically be damaged during the whole battle).
The Heartless: The Bittercold is made of everyone's fear and despair.