How high can the combo count go in Middle-earth: Shadow of Mordor? It's hard to say exactly, but YouTube's Rabbit's Respawn racked up 413 over a 15-minute span and theorizes that someone could go on forever, comboing his or her way across the map and back, without taking a lick of damage.
The key is the epic rune Tower of Defense equipped on your sword. This extends the reset time on your combo counter by a whopping 10 seconds. There is a lot you can do in 10 seconds, and if the next enemy is to far away from the last sucka you just killed, that's where the Elven Swiftness ability comes in. It tacks on a hit to your combo count assuming you properly time a button press with your vaults and jumps. It also makes Talion run faster.
A third vital ingredient would seem to be Shadow Strike, which teleports Talion to the foe he's just shot with his bow. Again, that covers a lot of ground, but more importantly, helps dispose of pesky archers more efficiently.
Rabbit's Respawn explains it all in the video above — this doesn't involve glitches or exploits, but it does require a higher-level character with some key abilities, and then commensurate skill on the part of the user. And for more on Shadow of Mordor, see our review. Polygon scored it a 9.5, calling the game an "ultimate rarity" for how it blends its narrative with the means for players to create one of their own.