Just like a true Final Fantasy game
Burning Chains When the chosen player loses the game, you win the game
Like most Magic: The Gathering cards, the value of Wrenn and Seven depends on a few consistent factors: its rarity, the printing and finish (regular or foil), its physical condition, and the set it was printed in (Duskmourn: House of Horror Commander)
Honorable Mention #2 (#12 Overall) - Bramble Familiar The Familiar is making the cut for casual and Fetch Quest is making the cut for Type Four, so they are both elevating it to here
The card maintains about a $5 secondary market price
It then wins the game by, you guessed it, milling the opponent until they have no cards left in their library