[Mr Migraine]

Originally Posted by vegietarian18

To start my turn, I disengage with 1 4th Mass, and he dies. Can I now choose to Wait Then Fire with 3 other 4th Mass? I think the answer is no, but there are two arguments you can make for yes: 1. the disengagement triggered while the 4th was on the space he started on, and so he never moved because he died on that space 2. because he's dead he's no longer in the 4th Mass, and so "none of the 4th Mass moved this turn".

This doesn't answer the question, but it's helpful for terminology:

Found here. Emphasis is mine.

Originally Posted by Heroscape FAQs 11.3

When does a figure actually receive a leaving engagement attack?
The leaving engagement attack occurs as soon as you declare that
the figure is moving onto a space that is no longer adjacent.
Remember, adjacency is checked only on spaces, not the area in
between spaces. Once you do that, your opponent can take a
leaving engagement attack. The figure is considered to be still on
the adjacent space when it receives or doesn't receive the leaving
engagement attack.

Does "declare it's moving" = "moved this turn"?