The middle two ranks flood: for your opponent's next 4 turns their bishops, rooks and queens cannot move through them, only into them.
You draft High Water Mark in Buff mode. Passive: it works on its own the whole time you hold it, with nothing to activate.
As a protection card, it shields a piece or bars squares from the opponent.
“The river remembers where it used to run.”
Affects your opponent's bishops, rooks, and queens.