Malcolm, Keen-Eyed Navigator

Flying
Whenever one or more Pirates you control deal damage to your opponents, you create a Treasure token for each opponent dealt damage. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")
Partner (You can have two commanders if both have partner.)

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}.)

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice this artifact: Draw a card.

Sky Diamond

This artifact enters tapped.
{T}: Add {U}.

Frantic Search

Draw two cards, then discard two cards. Untap up to three lands.

Oaken Siren

Flying, vigilance
{T}: Add {U}. Spend this mana only to cast an artifact spell or activate an ability of an artifact source.

Hierophant's Chalice

When this artifact enters, target opponent loses 1 life and you gain 1 life.
{T}: Add {C}.

Altar of the Pantheon

Your devotion to each color and each combination of colors is increased by one.
{T}: Add one mana of any color. If you control a God, a Demigod, or a legendary enchantment, you gain 1 life.

Lantern of Revealing

{T}: Add one mana of any color.
{4}, {T}: Look at the top card of your library. If it's a land card, you may put it onto the battlefield tapped. If you don't put the card onto the battlefield, you may put it on the bottom of your library.

Cryptic Serpent

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

Mirrorshell Crab

Ward {3} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {3}.)
Channel — {2}{U}, Discard this card: Counter target spell or ability unless its controller pays {3}.

Daze

You may return an Island you control to its owner's hand rather than pay this spell's mana cost.
Counter target spell unless its controller pays {1}.

Decanter of Endless Water

You have no maximum hand size.
{T}: Add one mana of any color.

Blue Elemental Blast

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

Gearseeker Serpent

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
{5}{U}: This creature can't be blocked this turn.

Consider

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

Bonder's Ornament

{T}: Add one mana of any color.
{4}, {T}: Each player who controls a permanent named Bonder's Ornament draws a card.

Shipwreck Looter

Raid — When this creature enters, if you attacked this turn, you may draw a card. If you do, discard a card.

Talas Scout

Sojourner's Companion

Affinity for artifacts
Artifact landcycling {2} ({2}, Discard this card: Search your library for an artifact land card, reveal it, put it into your hand, then shuffle.)

Darksteel Ingot

Indestructible (Effects that say "destroy" don't destroy this artifact.)
{T}: Add one mana of any color.

Thought Vessel

You have no maximum hand size.
{T}: Add {C}.

Cloud Pirates

Flying
This creature can block only creatures with flying.

Counterspell

Dazzling Denial

Counter target spell unless its controller pays {2}. If you control a Bird, counter that spell unless its controller pays {4} instead.

Kitesail Corsair

This creature has flying as long as it's attacking.

Guardian Idol

This artifact enters tapped.
{T}: Add {C}.
{2}: This artifact becomes a 2/2 Golem artifact creature until end of turn.

Dispel

Brainstorm

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

Brinelin, the Moon Kraken

When Brinelin enters and whenever you cast a spell with mana value 6 or greater, you may return target nonland permanent to its owner's hand.
Partner (You can have two commanders if both have partner.)

Star Compass

This artifact enters tapped.
{T}: Add one mana of any color that a basic land you control could produce.

Spell Syphon

Counter target spell unless its controller pays {1} for each blue permanent you control.

Capsizing Wave

Return target creature to its owner's hand. (Then exile this card. You may cast the creature later from exile.)

Sword Coast Serpent

This creature can't be blocked as long as you've cast a noncreature spell this turn.

Sword Coast Serpent // Capsizing Wave

Inherited Envelope

When this artifact enters, the Ring tempts you.
{T}: Add one mana of any color.

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Somber Hoverguard

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

Aethersnipe

When this creature enters, return target nonland permanent to its owner's hand.
Evoke {1}{U}{U} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Everflowing Chalice

Multikicker {2} (You may pay an additional {2} any number of times as you cast this spell.)
This artifact enters with a charge counter on it for each time it was kicked.
{T}: Add {C} for each charge counter on this artifact.

Talas Merchant

Flywheel Racer

Vigilance
{T}: Add one mana of any color. Activate only if this permanent is a creature.
Crew 1 (Tap any number of creatures you control with total power 1 or more: This Vehicle becomes an artifact creature until end of turn.)

Blitzball

{T}: Add one mana of any color.
GOOOOAAAALLL! — {T}, Sacrifice this artifact: Draw two cards. Activate only if an opponent was dealt combat damage by a legendary creature this turn.

Mechanozoa

When this creature enters, tap target artifact or creature an opponent controls and put a stun counter on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)
Warp {2}{U} (You may cast this card from your hand for its warp cost. Exile this creature at the beginning of the next end step, then you may cast it from exile on a later turn.)

Draconic Lore

This spell costs {2} less to cast if you control a Dragon.
Draw three cards.

Prying Eyes

Dragonstorm Globe

Each Dragon you control enters with an additional +1/+1 counter on it.
{T}: Add one mana of any color.

Myr Enforcer

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)

Steelfin Whale

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
Whenever an artifact you control enters, untap this creature.

Firemind Vessel

This artifact enters tapped.
{T}: Add two mana of different colors.

Drowned Diner

When you unlock this door, draw three cards, then discard a card.
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Meat Locker

When you unlock this door, tap up to one target creature and put two stun counters on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Meat Locker // Drowned Diner

Foil

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

Island

Mana Geode

When this artifact enters, scry 1.
{T}: Add one mana of any color.

Thassa's Bounty

Draw three cards. Target player mills three cards.

Ponder

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

Disruption Protocol

As an additional cost to cast this spell, tap an untapped artifact you control or pay {1}.
Counter target spell.

Mental Journey

Draw three cards.
Basic landcycling {1}{U} ({1}{U}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Treasure Cruise

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Draw three cards.

Scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Draw a card.

Fractured Powerstone

{T}: Add {C}.
{T}: Roll the planar die. Activate only as a sorcery.

Quicksilver Behemoth

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
When this creature attacks or blocks, return it to its owner's hand at end of combat. (Return it only if it's on the battlefield.)

Read the Tides

Choose one —
• Draw three cards.
• Return up to two target creatures to their owners' hands.

Spell Pierce

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

Sleight of Hand

Look at the top two cards of your library. Put one of them into your hand and the other on the bottom of your library.

Lórien Revealed

Draw three cards.
Islandcycling {1} ({1}, Discard this card: Search your library for an Island card, reveal it, put it into your hand, then shuffle.)