Counterspell

Spell Pierce

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

Spellstutter Sprite

Flash
Flying
When Spellstutter Sprite enters, counter target spell with mana value X or less, where X is the number of Faeries you control.

Spire Golem

Affinity for Islands (This spell costs {1} less to cast for each Island you control.)
Flying

Brainstorm

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

Faerie Miscreant

Flying
When Faerie Miscreant enters, if you control another creature named Faerie Miscreant, draw a card.

Mutagenic Growth

({G/P} can be paid with either {G} or 2 life.)
Target creature gets +2/+2 until end of turn.

Snap

Return target creature to its owner's hand. Untap up to two lands.

Faerie Seer

Flying
When Faerie Seer enters, scry 2. (Look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Moon-Circuit Hacker

Ninjutsu {U} ({U}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever Moon-Circuit Hacker deals combat damage to a player, you may draw a card. If you do, discard a card unless Moon-Circuit Hacker entered this turn.

Brinebarrow Intruder

Flash
When Brinebarrow Intruder enters, target creature an opponent controls gets -2/-0 until end of turn.

Of One Mind

This spell costs {2} less to cast if you control a Human creature and a non-Human creature.
Draw two cards.

Ninja of the Deep Hours

Ninjutsu {1}{U} ({1}{U}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever Ninja of the Deep Hours deals combat damage to a player, you may draw a card.