=> player.CurrentHp.Value --); player.CurrentHp.SubscribeToText(text); } public class Player { public IReactiveProperty<int> CurrentHp {get; private set;} public bool IsDead {get; private set;} public Player() { CurrentHp = new ReactiveProperty<int>(10); CurrentHp.Where(x => x <= 0) .Subscribe(_ => IsDead = true); } } Presenter Model