Forerunner armor capabilities 1

“The Forerunners move fast, but slowly things change and their armor doesn't like them and then it tries to kill them. The Forerunner who is a prisoner is crushed by his armor—it just squeezes him to death, like a bug who squashes itself. “The other two shed their armor and it writhes all over, kicking up ashy dust, but it still tries to reach out and kill them, kill me—but they grab me up fast and carry me away.
(Halo:Primordium; Ch.20)