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.

Sol Ring

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."

Prodigal Sorcerer

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

Island

Mox Ruby

Ancestral Recall

Counterspell

Fireball

This spell costs {1} more to cast for each target beyond the first.
Fireball deals X damage divided evenly, rounded down, among any number of targets.

Timetwister

Each player shuffles their hand and graveyard into their library, then draws seven cards. (Then put Timetwister into its owner's graveyard.)

Black Lotus

{T}, Sacrifice Black Lotus: Add three mana of any one color.

Unsummon

Return target creature to its owner's hand.

Volcanic Island

Lord of Atlantis

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

Blood Moon

Psionic Blast

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

Mox Sapphire

Mountain

Braingeyser

Time Walk

Wheel of Fortune

Each player discards their hand, then draws seven cards.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Control Magic

Enchant creature
You control enchanted creature.

Clone

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

Library of Alexandria

{T}: Add {C}.
{T}: Draw a card. Activate only if you have exactly seven cards in hand.