I'd agree with Chris' evaluation of zombie survival 'em up Dying Light in that, yes, there is a lot of fun to be had that's ever-so-slightly ruined by a clunky story and the odd technical issue. But in terms of post-release updates, developer Techland has gone over and above the call of duty as, some two years on, Dying Light now has eye-tracking support.

You'll need a Tobii EyeX Controller for it to work, however the game's latest patch introduces 14 different eye-tracking options designed to make evading undead baddies by way of parkour more efficient and more enjoyable.

Here's Techland's director of research and technology development Paweł Rohleder on how eye-tracking works in Dying Light:

As covered by Rohleder there, the above video's description breaks down exactly what investing in Dying Light's eye-tracking promises players:

Clean UI

Extended view

Auto pause

Dynamic light

Automatic interaction with gaze

Flashlight control

Multi-throw with gaze

Aim with gaze

Throw with gaze

Interact with gaze

Zombie awareness

Vault with gaze

Climb with gaze

Auto-climb when sprinting

From a personal standpoint, flashlight control seems like the most practical use of the technology. In fast quick-fire combat, I'm not sure I trust my gaze to work quicker than my hands, however being able to scope out appropriate escape routes when overwhelmed via my line-of-sight sounds peachy.

Dying Light's The Following Enhanced Edition—which includes its base game and The Following DLC—is on currently sale as part of The Humble Store's Winter Sale for £15.99/$19.99.