How does "auto-resolve" work in battles?

Question

Oftentimes I'm not quite in the mood to enter a whole battle sequence, and my army significantly outnumbers that of the enemy, so I'll just use auto-resolve to get it over with (it's that button in the middle of the interface right before a battle). However, I'm always uncertain if I should use it for the less one-sided battles (that I still sometimes don't feel like doing), so I was wondering: how does auto-resolve work?

I realize that there's some element of randomness involved, but what factors does the game consider when auto-resolving? Is it possible (this is one of my main concerns) that an auto-resolved battle, even if won, will result in me losing my general? Basically, what should I consider when thinking about the risk of using auto-resolve? I'm pretty sure it's more complicated than that little green/red bar in the middle.

Answer 1

Should you have more than one general in your army it's quite possible to lose them in an evenly matched battle. With a singular general you may lose a larger portion of their squad, but otherwise it's highly unlikely to lose the general themself.

If you heavily outnumber the enemy you'll generally encounter less losses with an autoresolve than a manually controlled battle, even if it were on the easiest difficulty setting.

In an scenario where you yourself are outnumbered you're better off manually controlling your troops rather than autocompleting it, auto = zero chance of success in such a case, whereas with manual control it's still possible to achieve victory.

The autoresolve purely deals with numbers, not terrain or the like, defending forces are given a numbered boost if in fortifications, and attacking forces counterboosts for siege weapons. A slight variance in outcomes from a random number generator for each smaller outcome of individual troops makes some small differences but that's all.

Also the level of difficulty set for the enemy ai can make a large difference, a singular ranged troop behind fortifications can fight off a full army to a timeout victory on the lowest difficulty, whereas on higher difficulty or with an autoresolve that's not possible.