Nintendo trolls you.

(randomly playing Zelda)

Me: FINALLY! I GOT 300 RUPEES! JUST ENOUGH FOR MY WALLET!

Navi: OH LOOK LINK HEY LINK LOOK, A TREASURE CHEST!

Me: Shut up, Navi. (opens chest)

Navi: YOU GOT A SPECIAL RUPPEE! IT IS WORTH 300 RUPPEES! THIS IS THE ONLY TIME IT APPEARS IN THE ENTIRE GAME!

Me: