Adventurous Apprentice

When Adventurous Apprentice enters the battlefield, it studies. (Reveal the top card of your library. If it's an instant or sorcery, you may put it
into your hand. If you don't, or if the revealed card
isn't an instant or sorcery, put a knowledge counter on
this creature.)
Whenever Adventurous Apprentice attacks or
blocks, if it has a knowledge counter on it, you
gain 2 life.