I dont know it's a bug or what? My hero's alive and i received victory should have gone more till my all hero's die.
Is this happened only once, or more times ?? If this is one time, than maybe accidentally you pressed "End Battle" (happened few times to me, and i didn't noticed it at first) and that's why battle ended. But if this is repeating than try to record whole run, and than support will have better way to check it.
And one more thing, please write on which platform it happened, just to make sure.
We never get the maxed damage that we should get from ember army cause it always stops when at stage 26. I wonder IGG adjusted it for us not to get the maxed score we want. None of us on Windows getting more than 700 million damage.