The reanimate at will thing makes this retarded.
I was going to do a whole write-up on how to set up your layers of indirect, to stalling and fighting them until you can counterattack quoting actual used tactics from Vietnam on an enemy assault with superior numbers yet no indirect who is knowing trying to 'grab you by the belt' to fight, all the way through stalling maneuvers and QRF utilization a la Otto Carius and tipping Heinz Guderian's method of using fast moving assets (we'd use cavalry supported by dragons in our scenario) to break the now stalled lines and isolate pockets.
But fuck all that. Due to the reanimation thing you basically have 2 realistic choices:
- Develop an intel chain on the ice king. Once its known where he is and the size and location of his forces, start a guerrilla type diversionary attack on his assets to where he would commit some, but not all of his forces to. Do this as many times as possible, gauging the size of response each time and finesse this to get as much of his forces deployed, separately, while keeping command (ice king) at home. While the majority of his army is deployed elsewhere fixing 1000 little problems, send a force to kill him directly.
- Assassinate him
Anything else is retarded at face value as you cannot win against an enemy that can die and come back to life at will, unless I'm misunderstanding as to how this works.