Multiplayer video games, or a "multiplayer" game is a group of games in which the same game environment can play multiple players at the same time. We divide them into two basic groups, offline and online multiplayer games. This paper focuses primarily on the online kind of multiplayer games. They are an integral part of most of today's video games due to their unique features. They provide a very deep social component that can expand with the quality community of gamers beyond the edges of the game, social networks, online video services, forums, players create fan-based games, there is even a part of players who are professionally engaged in competing gaming multiplayer games. Through history, gaining strength in computers, internet speeds, and gaming on many devices, the online gaming experience is unrecognizable compared to its humble beginnings. The aim of this paper was to design a simple multiplayer game created in Unity. This game will serve as a source of basic knowledge and concepts related to the implementation and the mode of operation of a multiplayer game. Students will be able to learn the functionalities of the Photon Networking Plugin for Unity that enables the online game through the hands-on testing of the game and later on the study of the implementation. The concept of the game relies on a well-known game of start and end joining games with rotating blocks that can be used to connect. Such a concept is seen in games where the goal is to connect the train cells or to connect the pipes to the water supply system properly. Multiplayer functionality is reduced to a cooperative game mode in which 2 players work together to solve the puzzle. As the puzzle itself does not quickly become repetitive, the games level will be randomly generated at each run. The implementation of the game itself proved to be demanding because of the previous generation of levels. When implementing an online component, it was important to have the necessary connections between the Photon server and the user who joins one of the created spaces on the server and later on the room. For a high-quality multiplayer experience, it was important to ensure the speed of the game played and its synchronization among the players. The experience of playing without delays and numerous anomalies is a priority when using an internet network that can be very unpredictable and variable. The design of the game due to the time limit of work has to be maximally simple. The game takes place in an energy plant and provides the basic audio and visual effects of a 3D virtual environment. Multiplayer games are an important part of the gaming market and grow year after year in popularity. Many of the complexity of the implementation will at first glance be discouraged from the realization of the online gaming idea, but if we look at all possible benefits provided by such an implementation, we can safely conclude that the time it takes to complete the online game is ultimately worth the money.