Yava
Katrina took a moment to ensure she upheld her composure. "You're a thinker, smart. I see why Keyhole sided with Netelle before." she mused, "Well then, I shall explain in full.
"There exists somewhere in this world a physical copy of both Truth and Fate, created at the beginning and end of the game, respectively. The game is won when they are united. The victor is given the ability to alter the Truth, drawing the world slightly closer to the ideal reality that they seek. For the Truth is the lens through which reality itself views the past, just as Fate is how it views the future.
"Victory cannot be achieved alone, and that's where other pieces like you come in.
"The four Stewards are the game's main players. We have several powers that distinguish us from the rest of humanity, but in the context of the game we are a middling piece. We are aware of Fate, which allows us to recognize other pieces. And we hold authority over Truth, allowing us to create new pieces in the form of Knights.
"The Seer is aware of the Truth in some regard and has the power to manipulate Fate.
"The Witch is a piece empowered by a costly transformation, making them very powerful both in and out of combat. The Truth protects them, making them very difficult to kill."
"The Prince is a mighty warrior guided by Fate. They are the most powerful piece, easily capable of dispatching any other in a direct confrontation. However, they tend to be fickle in nature, and convincing even one Prince to ally with you is often a victory condition in its own right.
"The Knight is attached to a specific Steward, there may only be one Knight to each steward at a time. They are a much weaker piece, but they can be transformed by their Steward to gain great power at the cost of their humanity.
"And finally there are Thieves like you. The weakest piece, so abandoned by both Truth and Fate that you defy the authority of other pieces. Effectively, your presence nullifies the game itself. This is a huge asset, allowing you to overcome any other piece if used appropriately. In particular, I suspect there is a very powerful Seer involved this time, and being invisible to her eye makes you extremely useful."