Giant Shark

This creature can't attack unless defending player controls an Island.
Whenever this creature blocks or becomes blocked by a creature that has been dealt damage this turn, this creature gets +2/+0 and gains trample until end of turn.
When you control no Islands, sacrifice this creature.

Unsubstantiate

Return target spell or creature to its owner's hand.

Crystal Spray

Change the text of target spell or permanent by replacing all instances of one color word with another or one basic land type with another until end of turn.
Draw a card.

Supplant Form

Return target creature to its owner's hand. You create a token that's a copy of that creature.

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.

Dandân

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

Accumulated Knowledge

Draw a card, then draw cards equal to the number of cards named Accumulated Knowledge in all graveyards.

Metamorphose

Put target permanent an opponent controls on top of its owner's library. That opponent may put an artifact, creature, enchantment, or land card from their hand onto the battlefield.

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.