Stealing the Diamond has 11 medals for the player to unlock.
Aggressive- Get the Aggressive ending.
Undetected- Get the Undetected ending.
EPIC- Get the Epic ending.
Fail Champion- Watch all 40 unique fails.
Failtastic- Fail a total of 55 times.
Like a D6- Choose the Jumble Hoppers three times.
tl;dr- Click the word "here" on the Portal gun fail screen.
BUNP- Click the Snap Neck option.
01100010- Click "OK" on one of the error windows in the Pokéball option.
It's a joke guys- Click the misspelled word on the Liquidificator's instruction sheet.
Obscure Medal- Click on every portrait you can find in the museum (Zeus-Rage, LOL wut pear, Angry Hitler, Pyramids, No U Luigi, Mah Boi 561 A.D., Leonidas IV 672 A.D.)