Tidal Warrior

{T}: Target land becomes an Island until end of turn.

Island

Exhaustion

Creatures and lands target opponent controls don't untap during their next untap step.

Seasinger

When you control no Islands, sacrifice Seasinger.
You may choose not to untap Seasinger during your untap step.
{T}: Gain control of target creature whose controller controls an Island for as long as you control Seasinger and Seasinger remains tapped.

Clone

You may have Clone enter as a copy of any creature on the battlefield.

Rebound

Change the target of target spell that targets only a player. The new target must be a player.

Vesuvan Doppelganger

You may have Vesuvan Doppelganger enter as a copy of any creature on the battlefield, except it doesn't copy that creature's color and it has "At the beginning of your upkeep, you may have this creature become a copy of target creature, except it doesn't copy that creature's color and it has this ability."

Fog Bank

Defender (This creature can't attack.)
Flying
Prevent all combat damage that would be dealt to and dealt by this creature.

Air Elemental

Flood

{U}{U}: Tap target creature without flying.

Archivist

Floodgate

Defender
When Floodgate has flying, sacrifice it.
When Floodgate leaves the battlefield, it deals damage to each nonblue creature without flying equal to half the number of Islands you control, rounded down.

Confiscate

Enchant permanent
You control enchanted permanent.

Meddle

If target spell has only one target and that target is a creature, change that spell's target to another creature.

Volrath's Curse

Enchant creature
Enchanted creature can't attack or block, and its activated abilities can't be activated. That creature's controller may sacrifice a permanent of their choice for that player to ignore this effect until end of turn.
{1}{U}: Return Volrath's Curse to its owner's hand.