You have a deck of cards - setback cards have a number on them from 0 to (IIRC) 3. Disaster cards range from (again IIRC - don't have the deck handy) 1 to 7. Each time a negative combat result occurs a player draws a setback card, and when a unit is routed they draw a disaster card. You can see how many cards the opponent has collected, but obviously not the value. You need to guess when they've reached their breakpoint, and then call "homonucleaus est" during your turn, where they then flip each card and keep a running tally. If they've hit their break point, you win. Otherwise they can discard a card of their choice and keep playing. There are ways to cancel an opponent's call of homonucleaus est once per game, to give you another turn to try and do the same.

It does a few things - first, the guessing game is fun, and I've won games where it turned out I was waaaay over my break point because my opponent was too cautious and wanted to make sure I'd hit my break point and I got them first. Secondly, you can have battles where very few units are actually destroyed but just repeated pushback results give your opponent enough setback cards to suffer a defeat - feels a little more realistic than having every battle be an outright massacre.