Luna Lovegood

Whenever you cast an instant or sorcery, look at
the top two cards in your library.
You may put one of these into your hand. Put
the remaining cards at the bottom of your library.
{3}{u} roll a d-20 Create a Blibbering Humdinger
token with x/x, where x is equal to half the
number from the dice roll rounded up.
Oooh, look, a Blibbering Humdinger!