# isWin(for:) Returns a Boolean value indicating whether the current state of the game model reflects a win for the specified player. ``` optional func isWin(for player: any GKGameModelPlayer) -> Bool ``` ## Parameters `player` An instance of your game’s player class (a custom class implementing the [`GKGameModelPlayer`](/documentation/GameplayKit/GKGameModelPlayer) protocol) representing the player evaluating the game model. ## Return Value if this game model represents a winning state for the specified player; if the game has been won or has not yet concluded. ## Discussion If the game has been won or lost, a strategist evaluating the game model can avoid evaluating further moves in the game and can therefore plan a successful move more efficiently. For some games, merely identifying winning and losing states of the game model and using a sufficiently large [`maxLookAheadDepth`](/documentation/GameplayKit/GKMinmaxStrategist/maxLookAheadDepth) value is enough for a strategist to play the game well. However, you can improve both the game performance and the runtime efficiency of move planning by also implementing the [`score(for:)`](/documentation/GameplayKit/GKGameModel/score(for:)) method to distinguish the relative desirability of non-game-ending states. > Note: > This method is optional; however, your game model class must implement at least one of the ``doc://com.apple.gameplaykit/documentation/GameplayKit/GKGameModel/score(for:)``, ``doc://com.apple.gameplaykit/documentation/GameplayKit/GKGameModel/isLoss(for:)``, and ``doc://com.apple.gameplaykit/documentation/GameplayKit/GKGameModel/isWin(for:)`` methods. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)