(From Injustice)

Damian screams, "You're not Robin anymore! Stop telling me what to do!" and throws one of his kali sticks at Nightwing. Unlike before, Dick is unprepared for the attack and struck in the head.

You're next to Nightwing (you're Nightwing's ally), and right now, Nightwing is dazed. There's a piece of debris behind him, and if he falls, he will break his neck and immediately be killed. You have the chance to stop him from dying.