Unfortunately, there is no offline mode. Since Mech Arena is a real-time multiplayer game, Internet access is required to connect to other players. Currently, we are not planning to add offline mode to the game.
Please note that the quality of the Internet connection directly influences the game's performance. It will run properly only with a fast and stable Wi-Fi connection. Mobile Internet is not considered sufficient to maintain an error-free gaming process.
You can also find tips on how to fix loading issues in this article:
General Loading Troubleshoot.