Here. An Alternate Universe fantasy game with Steampunk and Magitek elements. Characters are citizens of a vast empire (not that kind), composed of a plethora of kingdoms — many of whom don't like each other. Add into that a number of factions with their own ambitions, and you have a recipe for high tension, chock-full of political intrigue.
There's also AU within the AU, as someone pitched the idea of having a Grail War in Dagaria and a few people jumped on it. Amusingly, this game's version of Arturia Pendragon has absolutely nothing to do with the Grail War this time. Yet.
Angels, Devils and Squid: There is a Heaven, a Hell, and a pit in the world crawling with Lovecraftian monstrosities and the undead. The latter is more or less the most relevant to day-to-day life.
Back from the Dead: Characters who are killed are sent to one of multiple afterlives, but they can return if they choose — be it through diplomacy, manipulation, or force.
Corrupt Church: The Church under Delacroix's reign - while many of the members are honest, The Pope solely seeks power and inquisitions are not uncommon.
Crystal Dragon Jesus: The Church is modeled after Christianity, and it's monotheistic, but it worships, amusingly enough, the Crystal King — who resides in the Crystal Palace.
Deadpan Snarker: Xykon's reaction to the incident at Stratholme? "I really don't like that I just got totally outshone by a card."
Dead Serious: Though nobody really mourns Black Mage, nor does anyone expect he won't stick around, the events surrounding his death make it count anyway.
Evil Versus Evil: The two most militarily important kingdoms are both run by Omnicidal Maniacs. Who hate each other. The only things keeping Zeon and Amestris from engaging in a war of mutual extinction are the threat of the Rift, the Emperor's political power, and the fact that both King Bradley and Char Aznable have more complex plots than simply killing each other.
We also have characters filling similar roles for others' plots, such as Athrun Zala, who served under a Char Clone in canon, and serves under the man himself here.
It's good to note there are an (unknown) number of afterlives possible - how exactly it works is kept very mysterious. Hell does, however, have Horny Devils.
Flat Earth Atheist: With the prevalence of multiple gods and their making appearances to mortals, any atheist in the game automatically falls into this trope.
For the Evulz: Team Evil. Xykon, in particular, set out to wreck plague prevention and research for no reason other than he could.
Mistaken for Cheating: After Mitsunari tries to clear up the above misunderstanding.
My Sister Is Off Limits: A variation. Cornelia is so protective of her sister that she disapproves of her having a relationship at all. Needless to say, she utterly disapproves of Euphemia's engagement (now marriage) to Athrun. It's a variation because Cornelia and Athrun barely even know each other.
Shades of Conflict: The first four major kingdoms in the game range from the typical white knights (Arturia's Britain) to the well-intentioned but potentially underhanded (Mitsunari's Sawa) to those with a veneer of nobility over genocidal tendencies (Char's Zeon) to people who employ NaziVampires as regular retainers and attack Hidden Elf VillagesFor the Evulz - but at least the Rift is contained and the trains run on time (Bradley's Amestris) to the openly honest conflict neutral Nameless States.
Euphemia ships Roy/Cornelia, much to her sister's chagrin. King Bradley does, too, but he just wants them to reproduce and bring more souls into Amestris.
Kira seems to ship Athrun/Euphemia, despite his own crush on Euphie.
Shout Out: These happen sometimes, usually to the characters' original canons. For example, Athrun Zala being sent to rescue his fiancée, and said fiancée — Euphemia li Britannia — jumping out a window to reach him.
Tarot Motifs: Each character finds themselves in the possession of three magical tarot cards, each of a different Major Arcana. These have various effects.