Serum Visions

Mana Leak

Counter target spell unless its controller pays {3}.

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.

Pteramander

Flying
{7}{U}: Adapt 4. This ability costs {1} less to activate for each instant and sorcery card in your graveyard. (If this creature has no +1/+1 counters on it, put four +1/+1 counters on it.)

Shore Up

Target creature you control gets +1/+1 and gains hexproof until end of turn. Untap it. (It can't be the target of spells or abilities your opponents control.)

Tolarian Terror

This spell costs {1} less to cast for each instant and sorcery card in your graveyard.
Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)

Island

Thought Scour

Target player mills two cards.
Draw a card.

Threads of Disloyalty

Enchant creature with mana value 2 or less
You control enchanted creature.

Disrupting Shoal

You may exile a blue card with mana value X from your hand rather than pay this spell's mana cost.
Counter target spell if its mana value is X.

Remand

Counter target spell. If that spell is countered this way, put it into its owner's hand instead of into that player's graveyard.
Draw a card.

Counterspell

Insectile Aberration

Delver of Secrets

At the beginning of your upkeep, look at the top card of your library. You may reveal that card. If an instant or sorcery card is revealed this way, transform Delver of Secrets.

Delver of Secrets // Insectile Aberration

Vapor Snag

Return target creature to its owner's hand. Its controller loses 1 life.