Plains

Snap

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

Ancient Den

Esper Cormorants

Memory Lapse

Counter target spell. If that spell is countered this way, put it on top of its owner's library instead of into that player's graveyard.

Island

Razortide Bridge

Razortide Bridge enters tapped.
Indestructible
{T}: Add {W} or {U}.

Wingcrafter

Soulbond (You may pair this creature with another unpaired creature when either enters. They remain paired for as long as you control both of them.)
As long as Wingcrafter is paired with another creature, both creatures have flying.

Deft Duelist

First strike
Shroud (This creature can't be the target of spells or abilities.)

Ethercaste Knight

Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)

Seat of the Synod

Stormcaller's Boon

Sacrifice Stormcaller's Boon: Creatures you control gain flying until end of turn.
Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)

Sighted-Caste Sorcerer

Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
{U}: Sighted-Caste Sorcerer gains shroud until end of turn. (It can't be the target of spells or abilities.)

Warded Battlements

Defender (This creature can't attack.)
Attacking creatures you control get +1/+0.

Gearseeker Serpent

This spell costs {1} less to cast for each artifact you control.
{5}{U}: Gearseeker Serpent can't be blocked this turn.

Preordain

Scry 2, then draw a card. (To 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.)

Lofty Denial

Counter target spell unless its controller pays {1}. If you control a creature with flying, counter that spell unless its controller pays {4} instead.