In order to run set of MUnit tests, they need to be grouped within a container such as: Magik project, product, module or a folder. It is recommended to create a separate module or project as a test container. Launching multiple tests is similar to running single test, but you need to select container in e.g. Project Explorer view and launch tests using Run As > MUnit Test action from context menu.
You can also create new MUnit launch configuration and run the tests from the specified container.
MUnit test launcher