Angst? What Angst?: Lann and Reynn have almost no memories; from their perspective they work up one morning and found everyone in town had disappeared, and a mysterious woman claiming to be god and a talking fox tell them to go to an alternate dimension to fight and imprison monsters. And for the most part they treat it as a fun adventure and constantly banter and chat like nothing is unusual about this at all. While we see Reynn does have some hesitation about things, there's no sign she's a Stepford Smiler putting on an act, she seems just as enthusiastic about traveling Grymoire as Lann is, she just doesn't accept everything she's told at face value and tries to ponder things out. Even after the Cogna are unleashed and they regain their memories, they continue to bicker and make jokes frequently and only get serious when the mood around them calls for it.
Base-Breaking Character: As per tradition for Final Fantasy games, both main characters get this. Some see both Lann and Reynn as either a charming and comedic duo or obnoxiously stupid (Lann) and borderline abusive (Reynn).
Big-Lipped Alligator Moment: In a dialogue exchange in Nine Woods Hills, after Tama explains about Mirage Mastery, the characters- one-by-one- break down laughing over the idea of "Master" Lann. It gets so contagious that Enna Kros randomly pops in and asks if she really chose the right people to save Grymiore before joining in the laughing too. It is, of course, never brought up again.
Broken Base: The game going for a more soft, whimsical tone is a major point of contention. Is it a relieving breath of fresh air for the franchise, or does it ruin what it means to be a Final Fantasy game?
Complete Monster: Brandelis is the King of Bahamut and a member of the Exnine Knights, a group dedicated to destroying worlds ruled by their Arch-Enemy Alexander. When Lann and Reynn open the Ultima Gate and release Brandelis into Grymoire, his forces spend the next hundred years extracting the souls of Grymoire's people, using them to power their fortress while their bodies become vessels for Brandelis's minions to cross over with. When Lann and Reynn return, Brandelis tricks them into opening the Ultima Gate again, unleashing the Cogna on Grymoire to cause mass destruction and death. Even in defeat, Brandelis refuses to go quietly and attempts to take the heroes with him as he's dragged back through the Ultima Gate. A cruel and vicious warlord who prefers to brutally annihilate his enemies over less-violent options, Brandelis is a genocidal fiend who would conquer and destroy all of Alexander's worlds if he could, and does so proudly.
Crosses the Line Twice: A lot of Reynn and Tama's treatment of Lann can reach this. The two very often make jabs at his stupidity and incompetence, some of which are rather mean, and they mock him more when he doesn't even understand they were insulting him. Then Lann says or does something to remind players he really is that stupid and incompetent sometimes, and in such cases he has it coming.
Designated Villain: Ifreeta and Shivalry. The game treats the two of them coming into Grymoire as a horrible crisis, and the Who's Who refers to them as "really bad apples". But when they appear they're no more dangerous or hostile than any other Mirage, and Shivalry is actually heroic. This may be intentional — Ifrit and Shiva dislike them more for personal reasons (the main one being the two are Rule 63 versions of them), so treating their crossing over into Grymoire may be intended as tongue-in-cheek. And even if it weren't, the manner in which they did so is itself enough to make them a bit on the villainous side, as they had to resort to human sacrifice in lieu of being summoned properly.
Fanfic Fuel: As if other Final Fantasy games and Kingdom Hearts weren't already providing enough fuel for the idea, the game suggests that all Square Enix properties (or at least those two plus Xenogears, Einhander, and Sigma Harmonics) are part of a multiverse called the "Extraverse".
Eiko showed up at Cornelia during one of the intervene quests when the Cogna arrived. For those who don't look into secrets in Final Fantasy games, it won't make sense why Eiko is seen with Princess Sarah. But if they do, they will know the Easter Egg. What is Princess Garnet's a.k.a. Dagger's real name?
The passive ability "Strategic AP Hike" restores AP to the user when they hit an enemy's elemental weakness, and if multiple Mirages in a stack have it, the effect stacks. Depending on the AP cost of the ability, it's possible to regenerate more AP than you spent to attack in the first place. The only mitigating factor is that the ability is only on a handful of Mirages, but one of them is the Baby Paleberry, which can be acquired very early in the game and isn't a bad Mirage at all, and Shantotto's Mirajewel also has it for Reynn. In the late-game the ability is also possessed by Valefor and Nirvalefor, and the Master Moogle, letting you make a full stack where everyone has it.
In the Maxima version of the game, players can imprism a new Mirage, Dramut, either in a Murkrift on the Rainbow Shore or in a Coliseum battle. It's a Small Mirage, so it can be used in either Jiant or Lilikin stacks; it learns Fire, Blizzard, Thunder, and Light Flare (basically a weaker version of Flare); it has the support abilities Sizzle, Chill, Zap, and Stroll; it has three blank spots to put more abilities in; and it doesn't transmogrify into anything, so its board can be mastered fairly early. Also, the fact it learns all three base elemental spells means that it can be used to create powerful stack abilities, including Flare and Meteor. Dramut makes almost every other Small Mirage obsolete and will be powerful right into the endgame.
Moe: The artstyle is this, with all the chibi-fied characters and even traditional Final Fantasy summons and monster looking ridiculously cute.
Whenever Lann and Reynn are in their chibi forms or there are other chibi characters in them scenes can be really hard to take seriously, even when there's some dire threat or disaster or whatever looming.
Pretty much any time Lann says "honk", especially during more serious and somber scenes.
This game marks one of the first mainstream appearances of a female Ifrit, but the concept has been around for a while. An "Ifreeta" card shows up in Mobius Final Fantasy, a game released earlier in 2016 in the US,note Though she's much more humanoid there. and certain incarnations of Ifrit have been depicted as female in certain spin-offs and crossover games, such as Million Arthur, which had a card named Heatra, who was basically a gender-bended, less animalistic version of Final Fantasy X's Ifrit.
Periphery Demographic: The creators have stated that this game was made to try to appeal to the younger crowd, as the franchise wasn't exactly very popular with them. In spite of this, the game caught the eye of veteran Final Fantasy fans for using the classic battle system, which many have been clamoring for the series to use again after the shift to a more action-oriented fighting style.
Play the Game, Skip the Story: Pairing with the Periphery Demographic. Eventually the cliches dull into Narm Charm, the jokes (occasionally) hit their mark, and overall the experience is pleasant enough to endure for the gameplay. In general, the game is highly rated for its gameplay; quite a few comparisons to Kingdom Hearts have been made (and not coincidentally).
Polished Port: The Maxima port for the Switch is a portable version of the console releases, but with added content (which can be bought as DLC for other versions, but still). The Sora DLC isn't on the Switch version, though.
The Scrappy: There are fans who find Tama to be extremely the-annoying, partly due to her the-Verbal Tic.
Sidetracked by the Gold Saucer: Four minigames are required to be completed as part of the late-game, and can be played at any time afterwards in the twins' room.
Sandstalker: Terra, Vivi, and Shelke hunt down a Security Eye, Entom Guard, and War Machine on a grid in Figaro.* Complete this without any casualties, in twenty turns or less, via the Intervention Quest, to unlock a scene with Maduin and his memento
Nebula Storm: Lightning dashes through the Nether Nebula, fighting off Fritts, Bablizzes and Zaphyrs in the process.* When played as part of the Intervention Quest, this must be completed within sixty seconds without pausing to get the fight with Ramewl afterwards
Whack-A-Cactuar: Reynn stands in the middle of a ring of Cactuars and punches as many as she can.* The first time this is played as part of the Intervention Quest, the Cactuar Conductor is the lone target and must only be hit once to clear.
Einhänder Invasion: Tidus rides atop Valefor and shoots down Einhänders with Blitzball kicks.* The first time this is played as part of the Intervention Quest, a single hit on the sole Einhänder will clear it.
Maxima adds the simply-named Fishing: Lann, Noctis, and Reynn hook Sharquals on the pier at Besaid in an effort to catch the Lord of the Sea.* Successfully hook Leviathan to unlock Noctis' Champion Jewel.
Slow-Paced Beginning: A common criticism of the game among reviewers and fans is the pacing of the story. The first half of the game is spent setting up plot points to be explored, but doesn't really go into detail on them, so things move along at a slog with neither the characters nor the narrative getting more development. It isn't until Chapter 20 hits that the story really kicks into high gear, and it does so in the form of Info Dumps that can feel like the game is trying to make up for lost time squeezing all the plot into its back end.
That One Boss: Brandelis, in all his forms — even for the Big Bad, he is merciless. He always has a ton of HP, is ridiculously fast (so much so that even with Haste, your party members will barely keep up with him), gets faster as his HP decreases, and is immune to all status ailments and has no elemental weaknesses. In his first two fights he has Dispelga to remove your buffs anytime he likes, numerous elemental party-hitting attacks (so the odds are high that he has something to hit your elemental weaknesses), and non-elemental attacks too. Even as the Final Boss he doesn't let up, with "Arcarmament" attacks that deal heavy damage in his first form, and in his second form he has tier-four magic, status attacks, attacks to topple your stacks, Megaflare Cannon to deal heavy damage to the party, and as his HP decreases the turn countdown to when he uses Megaflare Cannon decreases too.
The intervention quest "The Five Cogna Lords: Figaro" requires you to play basically Battleship on a 5x5 board. You don't need to beat it to continue the story, but to get the Maduin Memento you have to beat it in 20 turns or less, without losing a single unit (your enemy's turns are included in that number, but since you can only win on your turn, you've effectively only got 10 turns). You and your enemy both have three units, with 1, 2 and 3 hp each, meaning you can only spare missing four times, as you need the other six to actually take down all their hp. It's so infamous that the notes on the Maxima expansion specifically state they made this mini-game easier.
Enna Kros is introduced in the game's prologue and sets the twins on their adventure. After this she completely disappears from the story until the ending, and in the Maxima version she's a post-game boss. Especially since late in the game Tama and Serafie explain that Brandelis and the Exnine Knights are basically Enna Kros/Alexander's arch-nemeses, it really seems she ought to be more directly involved in the plot.
Many of the Final Fantasy characters in the game aren't available to use as Champion Medals, including the likes of Rydia, Faris, Edgar, Quistis, Rikku, and Sherlotta. The Maxmima version makes this more egregious by adding more Champions and introducing Champion Jewels, but no new Champion Medals, and all of the Champion Jewels are for characters that were already available as Champion Medals anyway, so the unusable characters were overlooked twice.
This game has a bunch of characters from the main-numbered Final Fantasy games...along with Sherlotta and the Undead Princess. From Final Fantasy Crystal Chronicles: Echoes of Time. A spin-off game.
Similarly, Shelke is a bit of a surprise as she is from Dirge of Cerberus, a spinoff of Final Fantasy VII, and hardly the first thing that comes to peoples minds when they think FF7.
In terms of mirages, one of them is none other than Einhander. Yes, THAT Einhänder!
The titular mech of Xenogears is in the game as a mirage, going by the name "XG".
Sora's inclusion came as a huge surprise, especially since he's in all technicality a Disney character, which had otherwise prevented him from appearing in games such as Dissidia Final Fantasy.
Balthier, since up until then the game had absolutely nothing from Final Fantasy XII.
Unintentionally Unsympathetic: A few of the Intervention Quests can make you feel bad for whom you're supposed to be kicking the butts of.
First up is "The Ice Bridge", where Refia and Sherlotta ask Shiva to make an ice bridge, with Sherlotta being very aggressive about it when she goads the Mirage by calling her second-tier when she refuses. Unfortunately, you can't throw the battle to let Sherlotta get frozen by Shiva for her sass once you're forced to battle her.
Sherlotta gets another case of this in "Never Cross the Boss" when she and Refia beat up the Undead Princess and essentially get her to basically hustle customers to her inn (not that Undead Princess seems to mind, being bored anyway), the results of which can be seen in the Intervention Quest "A Grudge That Won't Budge".
Another is during "Treasure Island, Ahoy!" and "I Hate Lightning!" when Rikku visits the titular island, only to find it full of Mimics. Despite clearly being the aggressor by way of invading their territory, you're supposed to take Rikku's side against the Mimics and the Mimic Queen.
Woolseyism: The exchange in Besaid that leads up to Lann mimicking the infamous laughing scene from X is only in the English audio track.
Yes, THAT Einhänder!