Peasy operating a key pad

Over the chatter of teeth he heard a faint beep. Then two more. Then a fourth and fifth. He looked back down to the gate.
The lone ex was at the keypad for the gate controls. One finger from each hand stuck out. It stabbed at the keys with quick, precise movements.
It took MacLeod a few seconds to register what he was seeing. By then the red lights had started to flash. He saw movement between the fences as soldiers ran to safety. The exes outside the fence lumbered toward the gate with far too much purpose. Their teeth had stopped chattering. After two years of listening to the click-click-click of enamel he thought nothing could be more unnerving. A hiss filled the air, a sucking noise, and he realized they were breathing. A thousand exes were pulling air into their shriveled lungs.
When they spoke, it was in one voice.
“CALL ME LEGION,” roared the exes, “FOR I AM MANY.”

Excerpt From Ex-Patriots, pg 491
Peter Clines
https://books.apple.com/us/book/ex-patriots/id585738393