Due to Unreal Engine 5.5.1 issue, the game will not start if launched for the second time. This issue is not originated from the game project, it is an engine related problem.

As a meantime solution go to C:\Users\<username>\AppData\Local\BossRush2025\Saved and delete or remove every content from the BossRush2025_PCD3D_SM6.upipelinecache file. 

When this issue is resolved by UE, a new build will be released!

>>> UPDATE <<<<

A patch has been dropped! The game launch issue is solved!

Thank you for the understanding and support!