Skim Through

Look at the top X cards of defending player's library, where X is the number of cards in your hand. You may cast an instant among them without paying its mana cost, as long as its converted mana cost is X or less. Put the other cards on the bottom of defending player's library.
Cipher (Then you may exile this spell encoded on a creature you control. Whenever that creature deals combat damage to a player, its controller may cast a copy of the encoded card without paying its mana cost.)