Island

Petty Theft

Return target nonland permanent an opponent controls to its owner's hand.

Brazen Borrower

Flash
Flying
Brazen Borrower can block only creatures with flying.

Brazen Borrower // Petty Theft

Slither Blade

Mystic Sanctuary

({T}: Add {U}.)
Mystic Sanctuary enters tapped unless you control three or more other Islands.
When Mystic Sanctuary enters untapped, you may put target instant or sorcery card from your graveyard on top of your library.

Essence Capture

Counter target creature spell. Put a +1/+1 counter on up to one target creature you control.

Tempest Djinn

Flying
This creature gets +1/+0 for each basic Island you control.

Chart a Course

Draw two cards. Then discard a card unless you attacked this turn.

Negate

Spell Pierce

Counter target noncreature spell unless its controller pays {2}.

Scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Draw a card.

Dive Down

Target creature you control gets +0/+3 and gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Judge's Familiar

Flying
Sacrifice Judge's Familiar: Counter target instant or sorcery spell unless its controller pays {1}.

Curious Obsession

Enchant creature
Enchanted creature gets +1/+1 and has "Whenever this creature deals combat damage to a player, you may draw a card."
At the beginning of your end step, if you didn't attack with a creature this turn, sacrifice Curious Obsession.