http://www.techradar.com/news/shadow-of-wars-nemesis-system-is-at-once-brilliant-and-yet-incredibly-frustrating

When Middle Earth: Shadow of Mordor was first released back in 2014, it introduced the world to the 'Nemesis System', a gameplay mechanic that has Modor's hoards of Orcs responding dynamically to how you play the game. 

It will come as no surprise that its sequel, Shadow of War, features some big improvements to the Nemesis system. But in developer Monolith's eagerness to bolster the impressive system, it risks committing the cardinal sin of prioritizing it too much over the player's Orc-slaying.