Absurdly Sharp Blade: The Cutting Edge. Remember that "many things on this side [of the Veil] are more literal than you might imagine."
Fridge Logic: It is the line between theory and reality, between what is defined and what isn't, between open and locked, perhaps between knowing and not knowing. It seems Lady Death has given the key to the answer to all questions right at the start of the story but no-one is the wiser.
Exact Words: Cailyn refuses to surrender Cardinal's Soul Jar until she knows exactly what's going on. Now Cardinal can't take it back from her until the Umbra explain why they're after him... something they seem reluctant to do.
Fantasy Kitchen Sink: "Every myth, every belief, every dream, every nightmare, they all are residents of this side. The Veil separates the Every-Day from the Every-Daydream. If Humanity has dreamt it up, you'll find it lurking around here somewhere."
Powers That Be: So far two have been introduced - Lady Scarring, Aspect of Natural Healing, and Death herself; a possible third, the Earth Mother, has been mentioned, as has a for-sure fourth, Fate.
And, to be painfully exact, the term "Powers That Be" is used to describe what are apparently the most powerful beings in the comic's setting. There are 9 total, listed in the world description page: Bliss, Suffering, Order, Chaos, Energy, Matter, Life, Death, and Void.