Structurally, this game is similar to Slay the Spire: Traverse three semi-randomized branching paths capped by a static boss fight, fighting turn-based battles and collecting items along the way, concluding with a much smaller endboss level.
As a roguelike, you’re expected to play through multiple times with different characters in order to unlock various features such as new classes, class variations, individual character bonuses, a larger pool of possible equipment spawns, and a few relatively expensive general ease of use buffs (e.g. additional merchants). Like StS it manages to avoid feeling like these unlocks are a grind or the main purpose of playing; it’s perfectly possible to win with the starting characters on your first playthrough. The endboss changing after every win is a particularly nice touch that provides a remarkable amount of variety.
Combat is a pretty straight-forward affair with everyone (usually) getting one action a turn and each action having a different speed value which determines the action order. Where the strategy comes into play is that if you attack before your opponent, that attack will end up a guaranteed critical hit. Whereas criticals in most games are just a simple +% damage, here each attack has its own specific bonus and each critical hit also refills the equivalent of your mana pool (used for free actions or combo attacks). Which means making sure you attack before your opponent is essential to success. A task assisted by a stagger system which lets you delay an enemy’s action a certain number of times.
All in all it provides a remarkably well balanced mix of randomization and skill. Oh, but do be aware that the style of humor is extremely irreverent (think Cosmic Star Heroine).