How does this happen? Balanced Blitz?
#HOW?
hearty tide
minor topaz
Well that's a 100% roll with extremely high troop counts.
For any roll over 70 troops (non cap) the code uses an unknown estimation technique to determine the outcome of the battle.
I'd imagine it works something like this though (this is just my guess. Nobody except the devs knows how it works). If you have a high roll like that, it rolls a smaller battle that also has 100% odds for the attacker and just scales it up. So for example it would roll a 20v12. If the outcome of a 20v12 was a 8 troops lost for the attacker and 12 for the defender (a very realistic outcome) that would be a similar ratio to 893 to 1289.
Now this obviously is the exact opposit of how dice are supposed to work. The more individual dice rolls you have the more consistent the outcome. So an attacker and defender having 1000's of troops should make the outcome have a fairly close dispersion and using an estimation technique means you will have a much wider dispersion. This is also why caps are broken. Any cap roll over 35 troops uses the estimation technique