Island

Simic Guildgate

Simic Guildgate enters the battlefield tapped.
{T}: Add {G} or {U}.

Geth's Grimoire

Whenever an opponent discards a card, you may draw a card.

Unsummon

Return target creature to its owner's hand.

Yavimaya Coast

{T}: Add {C}.
{T}: Add {G} or {U}. Yavimaya Coast deals 1 damage to you.

Dimir Guildgate

Dimir Guildgate enters the battlefield tapped.
{T}: Add {U} or {B}.

Library of Leng

You have no maximum hand size.
If an effect causes you to discard a card, discard it, but you may put it on top of your library instead of into your graveyard.

Cognivore

Flying
Cognivore's power and toughness are each equal to the number of instant cards in all graveyards.

Mystic Snake

Flash
When Mystic Snake enters the battlefield, counter target spell.

Snap

Return target creature to its owner's hand. Untap up to two lands.

Golgari Guildgate

Golgari Guildgate enters the battlefield tapped.
{T}: Add {B} or {G}.

Boomerang

Return target permanent to its owner's hand.

Warped Devotion

Whenever a permanent is returned to a player's hand, that player discards a card.

Repulse

Return target creature to its owner's hand.
Draw a card.

Gaea's Skyfolk

Aether Burst

Return up to X target creatures to their owners' hands, where X is one plus the number of cards named Aether Burst in all graveyards as you cast this spell.

Megrim

Whenever an opponent discards a card, Megrim deals 2 damage to that player.

Forest

Withdraw

Return target creature to its owner's hand. Then return another target creature to its owner's hand unless its controller pays {1}.

Capsize

Buyback {3} (You may pay an additional {3} as you cast this spell. If you do, put this card into your hand as it resolves.)
Return target permanent to its owner's hand.