[Charles knew he should stay calm. Knew he should take a deep breath and take a step back and remember that Tony was looking to get a rise out of them all, that he was good at pushing buttons and he'd chosen this one for a reason, because he was trying to say something he wouldn't let himself articulate properly.

But all he could think about was Erik, screaming as his parents were dragged away from him, hearing the gun go off and his mother's body drop to the floor, starving, cold, filthy, being lined up with the other prisoners and only narrowly stopping the bullet that would have killed him, dragging himself out of the mass grave and running, running, trying to support Magda even though he was just as frail and weak as she was, his heart thundering so loudly in his chest he was worried it would give out before they were safe-

Charles knew everything about Erik. He'd seen what he'd been through through his eyes, his memories, and he remembered anger and pain and helplessness, and he couldn't be calm.

So, instead, he walked over to Tony and punched him in the face.]

You arrogant dick. [He was almost shaking with anger and adrenaline, but his voice was level, somehow.] You're lucky I haven't just dragged you down to Zero, or let everyone march down here and deal with you themselves. I don't care what you were trying to accomplish with this stunt, you will not bring that up with him again.