[AreaOfEffect]

There are three auto-route conditions:
1.Reaching turn 50
2.Less then 25% total army health
3.Less then 25% squad health (Each commander is it's own squad)

-The first 2 are army-wide auto-routes.
-All three are ignored by mindless (moral 50) and berserked (moral 99) units.
-Having a moral of 30 does not allow you to ignore any of these conditions, it only lets you ignore moral damage and normal moral checks.
-I think being immortal only lets you ignore the 2nd condition. Possibly the 3rd. (Only in positive dominion.)

In regards to assassination:
-A successful route by your commander will cause it to be dead, even if it is immortal and surrounded by positive dominion.
-Actually dying during an assassination will allow immortal units to be revived if in positive dominion.