Increase your Resistance Rank by raising Mettle against Skirmishes, Critical Engagements, and completing Story Quests on Bozjan's Southern Front.
Your resistance rank in Bozjan's southern front will only increase when you reach certain thresholds in Mettle and speak to Bozjan's commander at base camp. Unlike the traditional Final Fantasy XIV experience, Mettle cannot be earned by killing monsters. Instead, you need to clear "Skirmishes" (FATES by another name), "Critical Engagements" (tough boss battles you need to register for) and complete story quests that are unlocked each time you go up. in rank.
Skirmishes are the easiest to cultivate, as they constitute the bulk of the content of Bozjan's Southern Front. These appear often and their rewards scale based on FATE type, region, and current resistance rank (there are three regions in Bozjan's southern front - region two is unlocked at resistance rank 5 and region three when reaching rank 9). Critical engagements appear when certain criteria are met (usually the number of people in an area and the number of skirmishes cleared), and you must register to participate. The number of players who can participate is limited and you increase your chances of being selected by eliminating Skirmishes in Bozja. If this option is selected, you must select the invitation to teleport into the meeting.
There are special critical engagements called “Duals” that increase the amount of Mettle everyone gains in Bozja when completed, but these are difficult encounters to unlock and clear. First, you must beat a critical encounter without dying or getting hit by any of the avoidable attacks. Then you must register alongside all the other qualifiers, and only one person is selected. Finally, you have to face a boss who is more than capable of kicking your ass. These offer solid rewards to the person who clears them, but Duels tend to end in failure more often than not.
Story quests offer a good deal of Mettle, but they're limited. There is usually one for each resistance rank, and clearing them opens up not only more regions of the map, but a few features as well. If you farm for your Relic weapons, you'll want to follow them, as they tie into Bozjan's “Save the Queen” story in Final Fantasy XIV. Even if you don't care about relic weapons, these quests also unlock additional content on the South Front of Bozjan, so they're worth completing when you unlock them.
A few notes on Mettle and Resistance Ranks Very Quickly: Mettle can be lost to death after reaching Rank 5, but you won't lose Resistance Ranks. In other words, always visit the main camp and speak to the commander when you are able to increase your resistance rank. In addition, increasing your resistance rank increases your storage of lost actions and you will be able to recover better lost actions. Finally, enemy levels are based on resistance ranks, so you'll want to choose fights with enemies close to your rank if you don't want to lose your hard-earned Mettle.