Wall of Frost

Defender
Whenever Wall of Frost blocks a creature, that creature doesn't untap during its controller's next untap step.

Harbor Serpent

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Harbor Serpent can't attack unless there are five or more Islands on the battlefield.

Mighty Leap

Target creature gets +2/+2 and gains flying until end of turn.

Aether Adept

When Aether Adept enters, return target creature to its owner's hand.

Crystal Ball

{1}, {T}: Scry 2. (Look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Safe Passage

Prevent all damage that would be dealt to you and creatures you control this turn.

Sleep

Tap all creatures target player controls. Those creatures don't untap during that player's next untap step.

Stormtide Leviathan

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
All lands are Islands in addition to their other types.
Creatures without flying or islandwalk can't attack.

Armored Cancrix

Jace's Ingenuity

Plains

Air Servant

Flying
{2}{U}: Tap target creature with flying.

Maritime Guard

Azure Drake

Negate

Cloud Elemental

Flying
Cloud Elemental can block only creatures with flying.

Blinding Mage

Solemn Offering

Destroy target artifact or enchantment. You gain 4 life.

Scroll Thief

Whenever Scroll Thief deals combat damage to a player, draw a card.

Foresee

Condemn

Put target attacking creature on the bottom of its owner's library. Its controller gains life equal to its toughness.

Augury Owl

Flying
When Augury Owl enters, scry 3. (Look at the top three cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Water Servant

{U}: Water Servant gets +1/-1 until end of turn.
{U}: Water Servant gets -1/+1 until end of turn.

Conundrum Sphinx

Flying
Whenever Conundrum Sphinx attacks, each player chooses a card name. Then each player reveals the top card of their library. If the card a player revealed has the name they chose, that player puts it into their hand. If it doesn't, that player puts it on the bottom of their library.