The bank, the pool, and the rake.

Each game with a prize has a bank, a BNK escrow that holds its pool for the life of the game. In a paid room the pool is what the attempts fund: every all-pay charge adds to it, which is why a blind room can settle on the stakes it has gathered rather than on a fixed purse. The bank belongs to the game, not to a player, until it is paid out.

The house takes its share through a rake, and the design choice is to make that rake explicit. A published cut — a known percentage, or a capped or guaranteed pool stated up front — lets a player see exactly how the pool becomes the prize before they enter. At the close the rake is taken and the remainder is paid to the top entrants as diamonds, the prize currency.

There is a tempting alternative the reference design declines: seating undisclosed house players that can win prizes back from paying users. That is a hidden rake wearing a costume, and depending on the jurisdiction it can cross into deceptive or unlawful practice. The candid levers — a published rake, a minimum-participant threshold, a guaranteed floor — do the same economic work in the open, and the question of any house participation is left flagged for the chief architect and legal rather than wired in.