"Hasty Defense. Start with a random squad. Must be Captain to use this option."— Official game quote
The one of the earliest start options unlocked. This is also probably the worst deployment option, as, though you may get a super squad, you could also get a suicide squad. This makes planning strategies impossible, and it is generally a test of your skill to work with what you've got. However, this mode can be OK if you have the Westpoint Commendation, as you can just retreat those troops that you don't want.
What Is It Like?
There are no predetermined strategies, so it is a test of your intrinsic tactical skill to work out strategies with what you've got.