Adult Fear: Touched on in regards to Sylvia being kidnapped by Deus. Her father panicked during it, which lead to him getting sloppy and caught. Deus intentionally invoked this response just because it was amusing to see.
A Glass of Chianti: Invoked for psychological warfare purposes, though with strawberry juice instead.
An Offer You Can't Refuse: Hero to Villain example, Cass delivers one to Narcissa in regards to her rescuing her. Subverted in fact that Cassidy was going to rescue her from Deus anyway, but wanted to appear only doing it for selfish reasons to avoid appearing weak and ensure a future Enemy Mine.
Battle of Wits: The entire series is made of these. From strategical battles to physical fights, everything involves conflicting minds facing one another finding ways to accomplish their goals.
Being Good Sucks: As much as she wants to take the selfish route to destroy Deus' Batman Gambit, Cass realizes that it's not the right thing to do and will weight on her conscious. She goes on to admit some envy for Deus, only because he could do something so selfish and amoral without it bothering him while she can't.
Bitch Alert: Narcissa pulls this off right away in her very first lines combined with Incoming Ham.
Blade Brake: Gale stabs the top of the train to keep his balance.
Blasé Boast: Method Cass takes to dealing with Narcissa during their second Grandmaster confrontation
Bluff The Imposter: Narcissa tries this on Cassidy to test if she's really her or the Grandmaster disguised as Cassidy. It's pointless because Cassidy is not a master of disguise and only spread rumors that Grandmaster is.
Bring Them Around: Wynn's loyalty and protective side to Cass comes to head when Cass wants to rescue Narcissa. Cassidy is forced to outright that she will fight him if he stands in her way, knowing full well he won't harm her or let her go alone.
Born Lucky: Vincent believes all the Elite are this and that's to explain why everything works out in life for them or they can do so many things.
Half Truth: Whenever travelling around as herself, Cassidy uses these if questioned what she's doing.
He Who Fights Monsters: It's one of reasons Gale is against the existence of Grandmaster, believing that it'll eventually lead to this. Cassidy starts showing signs of this as it goes on in response to Deus, but it's not entirely sure where she'll end up yet.
Nepotism: Cassidy dislikes the thought that this is the only reason she'll one day run the Family Business. She chooses to work hard to prove that she deserves the position based upon her own talents, not family.
Paranoia Gambit: When confronted with Cornelius D. Knox for first time and he proves himself savvy to Cass methods, she employees this in response. His study of her backfires when he becomes so wrapped up in waiting for her trick that he can't focus on challenge in front of him.
Slouch of Villainy: Cassidy does anti-heroine variation while sitting on the edge of a building.
Social Darwinist: Arkland's Empire. The end goal is to create a perfect union through everybody's combined merit. If one fails to contribute, they fall in class and everybody is expected to adapt to situation.
Spit Take: Cassidy does this in response to Gale being on board.
Cassidy: Keep on the lookout for anybody in the crowd just trying to blend in, but seems to be doing more. Particularly if they are keeping an eye out for Narcissa or scanning around. It's just a hunch, but I suspect she may have assistance hidden within the crowd.
Wynn: No prob. Only thing I ask to know is why you think that?
Gale: Seeing as you've concluded your business with her, you should not be pressed to conduct some with me now, would you? I've just a couple of questions to ask.
Cassidy: It's an attractive offer, but I've no interest in discussing such matters on top of a train.
Gale: I'm sorry to say that was a rhetorical question. The rest of these won't be. If the setting is not to your liking, I could always arrange to take you elsewhere where you'd be more willing to chat.
Time Skip: 3 years pass between the origins story and start up of the plot. Said time itself was spent becoming a Classy Cat Burglar, building reputation, and seeking leads on Deus.
Too Slow: Cassidy's speed fighting style causes her to see others as this. She actually taunts Gale with this before escaping.
Train Job: Narcissa challenges the Grandmaster to complete one to steal Undine's Tear
Very Punchable Man: Zadak serves this point early on as means to show off Cassidy's skill.
Victory By Endurance: Two variations employ against each other. Deus is throwing multiple challenges at her meant to wear down for the final fight while Cass' holds out against them long enough while waiting for The Calvary to show up. Subverted when Cassidy reveals that Victory By Endurance was only Plan A and it's failure meant Plan B.
Walk Into Mordor: Cassidy uses this as tactical consideration (taking the path of least expected) for how enter Narcissa's room and travels across the top of a train.
Grandmaster Cass: “I couldn’t just waltz my way down the hall and into her room, now could I?”
What You Are in the Dark: Deus engineers a situation of this, fully using it to work off of a Batman Gambit he designed that can only be defeated by doing something selfish. Cassidy does consider selfish solution and wishes she could take it, but her morals won't allow it.
White Shirt of Death: Sharpe Security's white suits when worn by Jose Rocamora and Cornelius D. Knox
Would Hurt a Child: If it'll give him an advantage, Deus is perfectly willing to have this done. His Dragon willingly follows through with it, holding her by neck while dangling over the side off of boat all while Deus plays Manipulative Bastard.
Xanatos Speed Chess: Constantly used by Cassidy whenever things don't go exactly her way or she can't plan for something in advance
Your Approval Fills Me with Shame: Deus cheers on and encourages Cassidy to attack Knox after fight. She's completely repulsed by having to do so, though still follows through because it needs to be done.