You can store sets within each other to create sub-sets. This can be useful when you want to organize less important scene elements or actions within another heading.

To create a sub-set:

1. Create a new set containing the objects you want in the subset.
2. Select the set in the Scene browser.
3. Drag it on top of a second set.
4. Select Move to Set from the contextual menu.

The new set becomes a sub-set of the second set.

To remove a sub-set:

1. Select a sub-set in the Scene browser.
2. Drag the sub-set on top of the Sets root folder.

The sub-set displays under the root folder as a regular set again.