Under what conditions did you test it?
A lot depends on that...
The conditions, clearly, didn't favor either side:)
sand; primary skills at "0 0 0 0"; secondary skills - not related to battles; hero specialization - leaning towards magic (for example);
of course, without any additional morale or luck.
I created several groups - of 1, 10, 100, and 1000; turn priority - I tried it in turns. That's the gist of it...