Consider

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

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}.)

Force Spike

Counter target spell unless its controller pays {1}.

Echoing Truth

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

Dispel

Curfew

Each player returns a creature they control to its owner's hand.

Hydroblast

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

Blue Elemental Blast

Choose one —
• Counter target red spell.
• Destroy target red permanent.

Brainstorm

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

Spire Golem

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

Snap

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

Counterspell

Spell Pierce

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

Annul

Counter target artifact or enchantment spell.

Spreading Seas

Enchant land
When Spreading Seas enters, draw a card.
Enchanted land is an Island.

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

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.)

Negate

Island

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.)

Thought Scour

Target player mills two cards.
Draw a card.

Vector Glider

The Modern Age

(As this Saga enters and after your draw step, add a lore counter.)
I, II — Draw a card, then discard a card.
III — Exile this Saga, then return it to the battlefield transformed under your control.

The Modern Age // Vector Glider

Foil

You may discard an Island card and another card rather than pay this spell's mana cost.
Counter target spell.