Shadow Of War: 12 Tips & Tricks The Game Doesn't Tell You
7. Only Quests & Captain-Kills Give XP
How an oversight this big made it through I'll never know, but Shadow of War straight-up forgets to tell you precisely how the XP system works.
Which is to say, if you thought you could gallivant around the open world, killing thousands of orcs and ranking up in tow - none of the many regular grunts will give you any XP whatsoever.
Instead, the only ways to get XP are through Captain kills (found in the world) or through missions. Yes, killing Warchiefs and Overlords grants XP, but these are triggered from the map as icons. The only XP-giving orcs you can stumble upon are Captains.
Note that story missions give upwards of 10,000 XP once you're into the second Act, so if you need a boost to rank up your entire army in tow, prioritise these missions and targets. Your army is only as strong as Talion's level, so at some point you'll need to indulge in combat, story or otherwise.