Flooded Strand

{T}, Pay 1 life, Sacrifice this land: Search your library for a Plains or Island card, put it onto the battlefield, then shuffle.

To Arms!

Untap all creatures you control.
Draw a card.

Aether Vial

At the beginning of your upkeep, you may put a charge counter on this artifact.
{T}: You may put a creature card with mana value equal to the number of charge counters on this artifact from your hand onto the battlefield.

Unctus, Grand Metatect

Other blue creatures you control have "Whenever this creature becomes tapped, draw a card, then discard a card."
Other artifact creatures you control get +1/+1.
{U/P}: Until end of turn, target creature you control becomes a blue artifact in addition to its other colors and types. Activate only as a sorcery. ({U/P} can be paid with either {U} or 2 life.)

Plains

Corridor Monitor

When this creature enters, untap target artifact or creature you control.

Hangarback Walker

This creature enters with X +1/+1 counters on it.
When this creature dies, create a 1/1 colorless Thopter artifact creature token with flying for each +1/+1 counter on this creature.
{1}, {T}: Put a +1/+1 counter on this creature.

Dovin's Veto

This spell can't be countered.
Counter target noncreature spell.

Hallowed Fountain

({T}: Add {W} or {U}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Secure the Wastes

Create X 1/1 white Warrior creature tokens.

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Force of Negation

If it's not your turn, you may exile a blue card from your hand rather than pay this spell's mana cost.
Counter target noncreature spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Judge's Familiar

Flying
Sacrifice this creature: Counter target instant or sorcery spell unless its controller pays {1}.

Daring Thief

Inspired — Whenever this creature becomes untapped, you may exchange control of target nonland permanent you control and target permanent an opponent controls that shares a card type with it.

Clarion Spirit

Whenever you cast your second spell each turn, create a 1/1 white Spirit creature token with flying.

Island

Martyr's Soul

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
When this creature enters, if you control no tapped lands, put two +1/+1 counters on it.

Return to the Ranks

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Return X target creature cards with mana value 2 or less from your graveyard to the battlefield.

Caetus, Sea Tyrant of Segovia

Noncreature spells you cast have convoke. (Your creatures can help cast those spells. Each creature you tap while casting a noncreature spell pays for {1} or one mana of that creature's color.)
At the beginning of your end step, untap up to four target creatures.

Invasion of Segovia

(As a Siege enters, choose an opponent to protect it. You and others can attack it. When it's defeated, exile it, then cast it transformed.)
When this Siege enters, create two 1/1 blue Kraken creature tokens with trample.

Invasion of Segovia // Caetus, Sea Tyrant of Segovia

Meeting of Minds

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Draw two cards.

Knight-Errant of Eos

Convoke
When this creature enters, look at the top six cards of your library. You may reveal up to two creature cards with mana value X or less from among them, where X is the number of creatures that convoked this creature. Put the revealed cards into your hand, then shuffle.

Chief Engineer

Artifact spells you cast have convoke. (Your creatures can help cast those spells. Each creature you tap while casting an artifact spell pays for {1} or one mana of that creature's color.)