The main thing is that there must be an empty cell between our Azure Dragons and the enemy bird; the enemy Azure Dragons must support ours, and then the bug will work.
Cyclops are removed so that the Azure Dragons don't fly off to attack.
The bug only works if 1. The units are two-tile units. 2. The units are flying (I'm not sure about this, but I tried using Cerberuses instead of the bird – it didn't work).
Here's a version with auto-battle, just for fun :D I somehow thought of it before I thought of removing retaliation, but that's what happened :)
I also tried filling the field to the maximum for the sake of interest: https://imgur.com/a/ygeOH
The auto-battle freezes here, which is not surprising.
P.s. Those who want to can try adding 500 Titans or other ranged units to the enemy, the main thing is to trigger the bug. Then Mutar will start shooting at his own Azure Dragons, and it won't hit invisible units. Then it will just stand still, even though there are ranged units and our troops on the battlefield. If you get close, it will attack; if you stand two tiles away, it won't attack.
Another interesting point is that this bug somehow affects the "Sacrifice" spell. For example, you can sacrifice 1 Troglodyte and resurrect a Dragon :D
In general, the main advantage of this strategy is that the bug can be used against heroes who don't have a tent. I wonder if there are any battles in the same Meta-Tactics where this bug can be used? I would be interested to hear the opinions of those who have played.