Murmuring Mystic

Whenever you cast an instant or sorcery spell, create a 1/1 blue Bird Illusion creature token with flying.

Mental Note

Spell Pierce

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

Island

Echoing Truth

Return target nonland permanent and all other permanents with the same name as that permanent to their owners' hands.

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

Annul

Counter target artifact or enchantment spell.

Deep Analysis

Target player draws two cards.
Flashback—{1}{U}, Pay 3 life. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Weakstone's Subjugation

Enchant artifact or creature
When Weakstone's Subjugation enters, you may pay {3}. If you do, tap enchanted permanent.
Enchanted permanent doesn't untap during its controller's untap step.

Snap

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

Consider

Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
Draw a card.

Thought Scour

Target player mills two cards.
Draw a card.

Brainstorm

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

Hydroblast

Choose one —
• Counter target spell if it's red.
• Destroy target permanent if it's red.

Cryptic Serpent

This spell costs {1} less to cast for each instant and sorcery card in your graveyard.

Force Spike

Counter target spell unless its controller pays {1}.

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}.)