You see, if a captain is of a higher level than you, you can't have him fight for you. Instead, you'll need to use your powers to shame him after a prolonged battle. This reduces his overall level. Then you'll need to find him and fight him again in order to make him to join your ranks. This makes putting an army together in Shadow of War feel less like controlling a supernatural, undead assassin (who comes bundled with a grumpy elf lord spirit) and more like a grind-filled traditional role-playing game.
And its here that Shadow of War's micro-transactions come in. You can buy loot chests that let you get better weapons; experience boosts that allow you level up Talion quicker; war chests that grant you more powerful orcs; and bundles containing loot chests, experience boosts, and war chests.
Unlike other games that feature micro-transactions, you aren't constantly nagged to purchase them, and in fact you disable them completely by choosing to play offline. While there's an online component not too dissimilar to Metal Gear Solid V: The Phantom Pain's Forward Operating Base (FOB) feature that pits your forces against those online, it doesn't impact the progress of your campaign. Instead it simply allows you to increase your stats if your troops defend well enough against the onslaught.
Nonetheless, not once did we feel compelled to spend money to progress in Shadow of War, which is heartening. The razor sharp combat and Nemesis system ensured that each encounter was full of entertaining moments, such as a flying dragon hurling fire down on the battlefield, or the surprise arrival of a high-level orc captain and his retinue, or Forthog the Orc-Slayer showing up and slaying your target for you. Or in our case, all of these at once. Thanks to the procedurally generated nature of the game world, there are enough diversions to make sure you won't mind that you'll have to have another go at trying to convince a giant Olog to fight for you.
