Load mission or use "Play from here" option from inside the eden editor.
Run into enemy fire and die.
Switch to a remaining squad member.
Run into enemy fire and die again.
Press ESC and every other key on keyboard with no effect at all.
Press "Enter" to switch between 1st and 3rd person view, realizing that it's the only key that works now.
Lie on ground while remaining squadmates die.
Kill game with task manager.