Power Sink

Counter target spell unless its controller pays {X}. If that player doesn't, they tap all lands with mana abilities they control and lose all unspent mana.

Spell Blast

Counter target spell with mana value X. (For example, if that spell's mana cost is {3}{U}{U}, X is 5.)

Telekinesis

Tap target creature. Prevent all combat damage that would be dealt by that creature this turn. It doesn't untap during its controller's next two untap steps.

Serendib Efreet

Flying
At the beginning of your upkeep, Serendib Efreet deals 1 damage to you.

Sol Ring

Control Magic

Enchant creature
You control enchanted creature.

Strip Mine

{T}: Add {C}.
{T}, Sacrifice Strip Mine: Destroy target land.

Island

Dandân

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

Deep Water

{U}: Until end of turn, if you tap a land you control for mana, it produces {U} instead of any other type.

Power Leak

Enchant enchantment
At the beginning of the upkeep of enchanted enchantment's controller, that player may pay any amount of mana. Power Leak deals 2 damage to that player. Prevent X of that damage, where X is the amount of mana that player paid this way.

Maze of Ith

{T}: Untap target attacking creature. Prevent all combat damage that would be dealt to and dealt by that creature this turn.

Counterspell

Su-Chi

Lord of Atlantis

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

Mahamoti Djinn

Flying (This creature can't be blocked except by creatures with flying or reach.)

Braingeyser

Unstable Mutation

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 creature.

Feldon's Cane

{T}, Exile this artifact: Shuffle your graveyard into your library.

Hurkyl's Recall

Return all artifacts target player owns to their hand.

Energy Flux

All artifacts have "At the beginning of your upkeep, sacrifice this artifact unless you pay {2}."

Psionic Blast

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

Phantasmal Terrain

Enchant land
As Phantasmal Terrain enters, choose a basic land type.
Enchanted land is the chosen type.

Unsummon

Return target creature to its owner's hand.

Psychic Venom

Enchant land
Whenever enchanted land becomes tapped, Psychic Venom deals 2 damage to that land's controller.

Merfolk of the Pearl Trident

Mishra's Factory

{T}: Add {C}.
{1}: Mishra's Factory becomes a 2/2 Assembly-Worker artifact creature until end of turn. It's still a land.
{T}: Target Assembly-Worker creature gets +1/+1 until end of turn.

Blue Elemental Blast

Choose one —
• Counter target red spell.
• Destroy target red permanent.

Boomerang

Return target permanent to its owner's hand.

Mana Drain

Counter target spell. At the beginning of your next main phase, add an amount of {C} equal to that spell's mana value.