The entire fun part of the Korean focus tree (breaking away from China and creating the Ming/Greater Korea) is broken and requires commands to do because The requirement for both raids on the Qing border and invading the Qing require the Qing not to exist. I'm pretty sure this was supposed to check that the Qing do exist, but in its current state it softlocks you from going down the path (especially in mp where you can't use commands to ignore the requirements).