The subway platform is a symphony of panic. High above, the emergency sirens wail through the ventilation shafts, nearly drowned out by the simultaneous, shrill chirping of hundreds of mobile phones. Every screen in the station glows with the same crimson banner: EMERGENCY ALERT.

"THIS IS NOT A DRILL. EVACUATE NEW YORK CITY IMMEDIATELY. PROCEED TO THE NEAREST EVACUATION TENTS FOR TESTING AND TRANSPORT. DO NOT DELAY."

A woman near you drops her phone, her eyes wide as she looks toward the dark tunnel. You hear it before you see it: the sound of metal tearing and a chorus of guttural, inhuman shrieks. The crowd surges toward the turnstiles, but the gates are jammed. To your left, a stalled train sits with its doors partially pried open. To your right, a maintenance ladder leads up toward the street-level grates.

A shadow leaps from the top of a vending machine—a Runner, its limbs twitching with unnatural speed, eyes locked on the screaming crowd. You have seconds to move. What do you do?