This is a fully functional co-op multiplayer RPG sample called 'Boss Room' built by Unity Technologies to demonstrate patterns for Unity Netcode for GameObjects (NGO). The codebase is a server-authoritative client-server game with a state-driven architecture spanning connection management (Offline, Connecting, Hosting, Reconnecting), game phases (MainMenu, CharSelect, BossRoom, PostGame), and a data-driven action system. It uses VContainer for dependency injection, a custom pub/sub message bus (MessageChannel, NetworkedMessageChannel), and ScriptableObject-based configuration for characters, actions, and visual effects. The project integrates Unity Gaming Services (Authentication, Sessions, Relay) and includes reusable infra components like NetworkObjectPool, ClientNetworkTransform, and NetworkedLoadingProgressTracker. While primarily an educational sample, the code is production-quality and demonstrates advanced networking patterns such as action anticipation, client-side prediction masking, and persistent player sessions across scene transitions.