Forget the Tolkien association, and put aside its similarities with Assassin's Creed (for now). Shadow of Mordor is an Orc army on a disc, packaged with the tools and contextual excuses you need to wage a bloody one-man war against it.
It's surprising just how good and inventive Shadow of Mordor is. So many things are done right. The open world is packed with distractions from the main story, but almost everything you do feeds into it. Challenge modes, for instance, are presented as opportunities to "forge the legend" of the weapons in your arsenal. Completing them provides you with upgrades but also a sense that you are fulfilling some kind of prophecy.
But more integral to the expert blending of plot and emergent gameplay is the much-touted "Nemesis System", which populates the world with procedurally-generated Captains and Warchiefs that form the Orc command structure.
It is through this system that the game really shines. A huge part of SoM is about exploiting the Orcish lust for power, pitting Captain against Captain to shape battlefield politics in your favour.
For example; by gathering intelligence you can learn the combat weaknesses of individual Captains. You can then interfere with their internal squabbles, ensuring that the biggest pushover attains dominance. Defeat them, and they might survive, returning with a fitting disfigurement and some choice words about just how much they hate you.
Later on, you get the ability to "dominate" Orcs, making them your allies, which opens up another dimension of scheming.
SoM's story is split evenly between the Nemesis System and scripted missions. Each side of the equation depends on the other. It's beautifully designed. Unfortunately, cracks start to show toward the end, where things get a lot more cutscene heavy, boss fights start relying heavily on QTEs, and your previous machinations aren't shown to have any tangible effect on the final showdown.
But, as with The Lord of the Rings itself, it's more about the journey than the destination. Shadow of Mordor is a triumph, its final irony being that it's arguably the best and most pure Assassin's Creed game to date.
Version Tested: PS4