Proposed Canon
A commander other decision-making unit (like an Archon) can decide to surrender instead of fighting. This is like a parley, except it is one-sided and unconditional. Having surrendered, the unit (along with those under its command) becomes the prisoner of the other side in the hex.
- From what we've seen of unled units in text updates 24 and 39, it seems that they can only attack, and more importantly, don't want to do anything else.