Seedborn Muse

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

Beast Within

Destroy target permanent. Its controller creates a 3/3 green Beast creature token.

Wilderness Reclamation

At the beginning of your end step, untap all lands you control.

Eternal Witness

When this creature enters, you may return target card from your graveyard to your hand.

Arcane Denial

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.
You draw a card at the beginning of the next turn's upkeep.

Frilled Mystic

Flash
When this creature enters, you may counter target spell.

Sol Ring

Thought Sponge

Flash
This creature enters with a number of +1/+1 counters on it equal to the greatest number of cards an opponent has drawn this turn.
When this creature dies, draw cards equal to its power.

Mystic Snake

Flash
When this creature enters, counter target spell.

Counterspell

Rashmi, Eternities Crafter

Whenever you cast your first spell each turn, reveal the top card of your library. You may cast it without paying its mana cost if it's a spell with lesser mana value. If you don't cast it, put it into your hand.

Venser, Shaper Savant

Flash (You may cast this spell any time you could cast an instant.)
When Venser enters, return target spell or permanent to its owner's hand.