New Player Question --How am I Getting Flanked?

[Redfive]

Ah, yes I forgot about sneaking armies. I suppose that could be it though I'm surprised they were able to sneak two 50+ unit armies to two different provinces on the same turn.

Do you have to have units on patrol to find stealthers or is there a default chance as well?

I also suppose it could have been due to a teleportation spell, in which case I have to hand it to the AI. It wasn't as devastating as I first thought it would be but it is still quite a setback.

Also, there was a battle report but I didn't actually check the units to see what got me. If I see this sort of thing happen again you can be sure I'll check.

Also, since I'm asking questions: I received a battle report that my units had conquered a far off province so I went to investigate and found that indeed I had a new province and several commanders and troops garrisoned inside. How in the world does something like this happen? It turned out to be very fortuitous as I was able to help seal off a choke point to stave off AI advances but I'd like to at least know why it happened.