For example, a card might have a low converted mana cost and be a mythic but it might be just a vanilla green creature with two power and toughness
Weakness: Grass (x2) Resistance: none Retreat: 3 Rotom Lightning HP70 Basic Pokemon [L] Energy Draw: Search your deck for a Basic Energy card and attach it to this Pokemon
There are other cards that do that, too
The lower the bust rate, the better your odds of opening a decent box
However, Shigeki Morimoto, one of the game designers at Game Freak, secretly programmed Mew into the game as a joke among Game Freak Staff that only they would be able to obtain
Natural Order For 4 mana, Natural Order takes your worst green creature on the battlefield and turns it into the best green creature from your library