Timeshifted

{U}{U}, Sacrifice a Wizard: Counter target spell. Morph {U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time f...

Enchant creature Enchanted creature gets +3/+3. At the beginning of the upkeep of enchanted creature's controller, put a -1/-1 counter on that cr...

Flying White spells and black spells you cast cost {1} less to cast.

{T}: Draw a card and reveal it. If it isn't a land card, discard it.

Psionic Blast deals 4 damage to any target and 2 damage to you.

Lands you control are Plains. Nonland permanents you control are white. The same is true for spells you control and nonland cards you own that are...

{T}: Prodigal Sorcerer deals 1 damage to any target.

Pirate Ship can't attack unless defending player controls an Island. {T}: Pirate Ship deals 1 damage to any target. When you control no Islands, ...

When Ovinomancer enters the battlefield, sacrifice it unless you return three basic lands you control to their owner's hand. {T}, Return Ovinomanc...

Mistform Ultimus is every creature type (even if this card isn't on the battlefield).

{T}: Destroy target creature with islandwalk.

Other Merfolk get +1/+1 and have islandwalk. (They can't be blocked as long as defending player controls an Island.)

Trample Leviathan enters the battlefield tapped and doesn't untap during your untap step. At the beginning of your upkeep, you may sacrifice two ...

You may choose not to untap Giant Oyster during your untap step. {T}: For as long as Giant Oyster remains tapped, target tapped creature doesn't u...

Flying {U}{U}{U}: Regenerate Ghost Ship.

Flying

Sacrifice an enchantment: Auratog gets +2/+2 until end of turn.

Dandân can't attack unless defending player controls an Island. When you control no Islands, sacrifice Dandân.

Flanking (Whenever a creature without flanking blocks this creature, the blocking creature gets -1/-1 until end of turn.) {1}{W}{W}: Target Knight ...

{T}: Witch Hunter deals 1 damage to target player or planeswalker. {1}{W}{W}, {T}: Return target creature an opponent controls to its owner's hand.

First strike As long as Valor is in your graveyard and you control a Plains, creatures you control have first strike.

Protection from red Shadow (This creature can block or be blocked by only creatures with shadow.)

At the beginning of your upkeep, sacrifice Sacred Mesa unless you sacrifice a Pegasus. {1}{W}: Create a 1/1 white Pegasus creature token with flying.