So how about more honesty / transparency: Instead of continuing to re-roll, just abort the battle once an extreme outcome is hit:
Example:If the 1000 tests say that the attacker should survive with at least 3 units, simply abort the battle once the attacker has 3 units left. The defenders turn to the skull symbol all at once, and the 3 remaining attacker receive halo symbol on top to show that "Rambo"-mode was activated for them.
Similarly, if the 1000 test also say that the attack should win with at most 4 units, and the battle is over with 6 units surviving, then add another step where the first 2 attackers are turned into the defeated skull with a storm cloud on top of it.
So this still keeps the percentages true as KGB prefers, requires less computation than faking dice rolls, and is also much more transparent for players, so that they can intuitively learn the 90%-rule through watching battle replays (without the need to open the info box displaying actual dice rolls).
Oh, and while you're at it, please implement a skull with a dagger on top of it for units that got killed by ambush. Thanks! PS: Instead of the halo for rambo-mode, the skull with the storm cloud suffices:
* normal skull = killed normally in battle
* dagger skull = killed by ambush
* storm cloud = killed by pruning extreme luck
So in the first part of the example above, once only 3 attackers remains, the remaining defenders are turned into storm cloud skulls all at once. No halos icons needed, same information conveyed. Yay!