Dying Light's parkour is its strength. Zombie games are typically so rigid--not unlike the enemies that fill their corridors, malls, or islands--and it's good to be able to stretch your legs every once in a while. Sure, you're not going to be as agile as Mirror's Edge's Faith, but it helps make the otherwise ordinary world of Dying Light feel more exciting and original than it otherwise might be.
Running up walls opens up the world tremendously, mostly because of how easy it is to do. Simply hold down a bumper and you'll climb, just like you do in Assassin's Creed. I was able to use this to navigate the rooftops, jumping between buildings and avoiding zombies completely. When I ended up on a rooftop with one (I have absolutely no idea how he got up there, for the record) I opted to just kick him off and watch as he tumbled towards the ground below. Then I whipped out my grappling hook--which is actually more of a grappling gun--and zipped to a nearby building seamlessly.
Whereas some of Techland's other games have felt clunky, Dying Light is smooth and easy to control both with the movement and combat. The weapons feel weighty and impactful, and the addition of X-rays on powerful hits to show broken bones is a nice touch--especially since it actually causes the enemy to lose control of that limb. It all works together well, and should help to propel Dying Light to be one of the best first-person open-world zombie games of 2015. And yes, there are enough first-person open-world zombie games coming out in 2015 to say that.
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