*This achievement can't be obtained in conquest.
To get this achievement go to "start mission" and pick one of the yellow territories on the map, you can do invasion or stronghold. the emergency situation is when the yellow emergency screen pops up meaning that there is another team playing. You just have to win the battle to get the achievement.
It could take a while to find another team so the easiest way to get this achievement is to find a partner with a territory, and have them start a stronghold and search for their game by picking invasion. Just keep in mind that this must be done in stronghold / invasion NOT conquest.