During the endgame at Pandæmonium, Machina gets his ass handed to him by Rem, and only survives because his mask comes off before she can land the coup de grâce. When you remember that Machina got his focus from Qun'mi, a Secundus l'Cie, and Rem is filling in for Zhuyu, a Primus l'Cie, the Squishy Wizard beating the Mighty Glacier in a swordfight makes a little more sense.
Cater's Elementillery has three settings based on the direction of your analog stick; Flame Shot, Voltaic Shot, and Frost Shot. Flame and Voltaic Shots have a pause before the next shot, but Frost Shots have no such penalty. Of course, ice doesn't threaten to overheat your weapon, so she can fire off with impunity.
The placement of l'Cie brands on some of the Classmates Zero have interesting connotations:
Ace: His brand manifests over his right hand, in which he holds his cards. Of course, a gambler can't give away his game hand.
Deuce: Her brand manifests on her back. The way she walks when playing her flute brings to mind a marching band, which usually have big-ass flags attached to their backs.
Queen: Her brand manifests over her left arm, and she hold her sword in her right hand. The size and pattern of the brand are reminiscent of a shield.
At the start of the game, Ace is equipped with Blizzard BOM. Which doesn't make sense, because he just roasted a bunch of Militesi soldiers with what looked like Firaga RF. Come the secret ending, he's datingMutsuki.
A subtle one, but Machina has green eyes and Rem has red eyes. Later in the game, they become a White Tiger l'Cie and Vermilion Bird l'Cie, respectively.
After Machina becomes a l'Cie, notice that the front part of Machina's cape is still red, while the rest of his outfit turns white upon his putting on Qun'mi's mask. It goes to show that the real Machina is still in there somewhere.
Major background spoilers: Joker is always disguised - he's a Militesi soldier during Machina's Struggle, and he's an Akademeia legionary in a Camouflage Cloak when he appears as Support Personnel. Of course, a joker is a wild card - which, in a lot of card games, can sub in for anything.
During the opening fight with Qun'mi, Machina spends the whole fight trying to land a hit with his Bolt Rapiers, while Rem uses a combination of magic and her daggers. Machina is not allowed to use magic as a White Tiger, but nothing about the dominion stops anyone from using swords as well as spells.
During the escape from the Imperial Capital, Machina and Rem are playable from the beginning, despite reporting the sensation of a crystal jammer not moments before the mission starts; contrast with the Battle of Big Bridge, where Rem is unavailable until the jammer is destroyed. Well, the Rubicus reports that the crystal jammer targets the opposing crystal, rather than just nullifying all crystal links. Since the whole reason they need to flee is the death of Queen Andoria, most likely the jammer was targeting the Azure Dragon Crystal, leaving Vermillion Birds to cast freely.
Trey's Character Filibusters go off-topic right quick, right? WRONG. Pay attention to where he starts going with those:
When he and Deuce are talking to Ace about his dream on the bench, Ace mentions he can't remember what he was dreaming about. Trey starts describing the scientific explanation for human dreaming - most likely, he's trying to explain why Ace can't remember what he was dreaming about.
When he's talking to Cater about her déjà vu at the Abandoned House in Old Lorica, she's trying to figure out why she's having this inexplicable sense of familiarity. Trey believes that by explaining the cause of déjà vu, she'll be able to determine whether it's actually déjà vu or something more... Fantasian.
No, you don't want to fightSupersoldier Akkad - at least, the first time you see him. But given where he ends up, odds are good that you'll narrowly dodge at least ONE of his attacks. When you fight Gilgamesh at Big Bridge, the fighting style might seem familiar, but it doesn't really click until you go to Ultima Ground Zero for Ryid's request. Then you see The Lost. And you read the Rubicus entry on Milites' capture of the Black Tortoise Crystal. Akkad is a Lorican paladin. Militesi 'freaks' are Lorican survivors. Can you say Moral Event Horizon?
WAIT A SECOND. If the world of Orience has its inhabitants literally live by having their memories erased anytime any living being they know dies, then how does Class Zero gain experience?
If you meant by gain experience by learning from someone else that died before, then the answer is they learn everything, but not remembering from who they learned it.
Alternately, Kazusa's experiments prove that memories are stored within the flesh, as well as in the heart and mind - as far as combat experience goes, muscle memory can fill in when the mind isn't there.
Also, there are some missable scenes with Ace in the backgarden. You have to play as Ace and when you sit on the bench to rest, Ace starts to actually remember bits and pieces of his conversation with Izana. This seems to imply that your memories are still there, just buried deep in your subconscious. Talking to an orderly after Aria dies, the orderly says that she feels as if she is waiting for someone to come back and afterwards you unlock another chapter in the Rubicus showing how Aria died. There are also Cater's feelings of deja vu.
"Each city-state in the Lorican Alliance organized a troop of mounted paladins"- WAIT A SECOND. Mounted paladins? Loricans are huge, and if Atra and Enkidu are any indication, these guys wear plate mail that puts a Baron dark knight to shame. What do these guys ride?
Trained Great Tauricorns, maybe?
Actually, that makes a lot of sense. There are a lot of Doublicorn-style enemies in the Black Tortoise Crevasse and Ultima Ground Zero.
So Orience was stuck in the same spiral 600,000,000+ times because two fal'Cie were trying to open Etro's gate and kept resetting the spiral everytime they failed. Considering that Dr Arecia was using Class Zero, it makes sense that she will need to keep keep resetting and trying again and again until their souls became strong enough to become Agito and they could open the gates. But what about Gala? He wants to open the gates by sacrificing everyone in Orience so that the rush of souls would force the gates open. He should have been able to achieve this goal the first time Class Zero failed, and he slaughtered everybody in Orience.
Except, the rush of souls isn't enough to get the gate open. Yes, Orphan and Caius were stopped before they could try, but the resetting of the spiral indicates that killing everybody doesn't cut it. One would assume that Gala has since resorted to "the same, but more" while Arecia kept trying different approaches to Class Zero's sacrifice.
But surely after 600,000,000+ spirals, Gala can see that his method still isn't working?
Fal'Cie are stubborn bastards. Atomos and Dahaka were still running the same search when Fang and Vanille woke up as they were when they went to sleep; even Arecia had to be told things were different this spiral. Gala probably just didn't get the memo.
The above brings to mind another bit of Fridge Logic. Was Dr Arecia not keeping watch to see what Class Zero will do in this spiral? She is hoping to use them to open the gate after all. Why would she need to be told that they did things more differently this spiral?
It's all a matter of what she was focusing on, and what exactly was different. At the end of the spiral, their objective is to open Etro's Gate. Naturally, her focus would have been on the gate during Tempus; what was different this spiral was Class Zero - and, perhaps more reasonably, a whole frickin' lot of other people being willing to face death.
How did Machina and Rem not see each other at Akademeia for two months? Akademeia does not seem like a terribly large place.
Observation of the Rubicus, combined with Rem's claim that they met one another at a drill and Seven's observation that seeing a lot of the same class is a common - but not constant - occurence, indicates that Akademeia normally maintains a stricter schedule of training and lectures, and the war has resulted in the Agito Cadets' idling as seen in-game.