Arcane Laboratory

Each player can't cast more than one spell each turn.

Mystic Snake

Flash
When Mystic Snake enters, counter target spell.

Counterspell

Equilibrium

Whenever you cast a creature spell, you may pay {1}. If you do, return target creature to its owner's hand.

Forgotten Ancient

Whenever a player casts a spell, you may put a +1/+1 counter on Forgotten Ancient.
At the beginning of your upkeep, you may move any number of +1/+1 counters from Forgotten Ancient onto other creatures.

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.

Seedborn Muse

Untap all permanents you control during each other player's untap step.

Gaea's Skyfolk

Yavimaya Coast

{T}: Add {C}.
{T}: Add {G} or {U}. Yavimaya Coast deals 1 damage to you.

Weird Harvest

Each player may search their library for up to X creature cards, reveal those cards, put them into their hand, then shuffle.

Island

Forest

Aether Burst

Return up to X target creatures to their owners' hands, where X is one plus the number of cards named Aether Burst in all graveyards as you cast this spell.

Wash Out

Return all permanents of the color of your choice to their owners' hands.

Moment's Peace

Prevent all combat damage that would be dealt this turn.
Flashback {2}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)