The Savior

''The hero of the Hero. Who's saving whose hide now?''

Like what the slidetext said, the Cavalry is the person or people that rescue(s) the Hero and their friends when they're in need of rescue. They may be counted or responsible for many Ex Machina moments due to how they can seemingly show up out of nowhere with the greatest timing. It might not be the Cavalry's strict job to save people; they might just be obliged to do it because the ones they're saving are Utterly Helpless without the Cavalry. As it's the Cavalry's job to save the Hero, they likely won't get themselves into whatever problem the Hero did, like get trapped, captured by an enemy, or stuck on the side of a cliff. If they do get into trouble, the only thing that can save them and those who they failed to rescue can only be saved by another Ex Machina UnTrash or role at such a point.