Anytime you cast a spell that would trigger a prowess effect, Bria will make one of your creatures unblockable for the turn, letting you sneak in commander damage or even just regular damage through enemy lines
Hexplate Wallbreaker is intentionally balanced to only give you one extra combat step, but even then, it is a powerful piece of equipment
As far as what makes a cat, here's the criteria It's a cat . Cat-like behavior Large cats count, i.e
It can grow big depending on the number of creatures you control and creatures that ETB
In more corner-case scenarios, cards like Return to the Ranks or Rally the Ancestors can lead to instant kills with Flayer
Moreover, the Singleton nature of the deck enhances the effectiveness of the tutor ability on Case of the Stashed Skeleton