Mythical Unicorns and the Paladins that ride them.
It is true, Corporals are VERY rare, like pandas. I think there are only five or six Corporals in the entire United States Army.

Comic Dialogue
(If you have Wii Gloves for you wee little fingers it’s also electronic Braille.)

Dark Nessa: “Weekly?! What kind of group are you in? I’ve been volunteering for every group I could and haven’t racked up enough experience to get a secondary skill!”
Page Yatasha: “I’m not sure exactly who’s in our group, it’s kind of a group of groups…”
Dark Nessa: “Group of groups?”
Page Yatasha: “Sort of, my master’s the head of a Paladin Order…”
Dark Nessa: “Paladin order?! Paladins exist?! I thought they were a myth, like unicorns, or corporals in the army?!”
Page Yatasha: “Oh, they exist, they’re just rare, VERY rare.”
Page Yatasha: “In fact, I’d bet you’d be perfect to join my master’s order!”
Dark Nessa: “ME? A paladin? I dunno, I’ve always thought of myself as more of thief or scoundrel type…”
Page Yatasha: “You should meet my master, just to see if it’s something you’d like…”
Dark Nessa: “Hmm, sounds tempting…”
Page Yatasha: “Yes, very tempting, which is exactly why I think you’ll be a perfect fit for my master…”