Prosper, Tome-Bound

Deathtouch
Mystic Arcanum — At the beginning of your end step, exile the top card of your library. Until the end of your next turn, you may play that card.
Pact Boon — Whenever you play a card from exile, create a Treasure token.

Passionate Archaeologist

Commander creatures you own have "Whenever you cast a spell from exile, this creature deals damage equal to that spell's mana value to target opponent."

Tasha, the Witch Queen

Whenever you cast a spell you don't own, create a 3/3 black Demon creature token.
+1: Draw a card. For each opponent, exile up to one target instant or sorcery card from that player's graveyard and put a page counter on it.
−3: You may cast a spell from among cards in exile with page counters on them without paying its mana cost.
Tasha, the Witch Queen can be your commander.

Breeches, Brazen Plunderer

Menace
Whenever one or more Pirates you control deal damage to your opponents, exile the top card of each of those opponents' libraries. You may play those cards this turn, and you may spend mana as though it were mana of any color to cast those spells.
Partner (You can have two commanders if both have partner.)

Corsairs of Umbar

{2}{U}: Target Goblin, Orc, or Pirate can't be blocked this turn.
Whenever this creature deals combat damage to a player, amass Orcs 3. (Put three +1/+1 counters on an Army you control. It's also an Orc. If you don't control an Army, create a 0/0 black Orc Army creature token first.)

Nalfeshnee

Flying
Whenever you cast a spell from exile, copy it. You may choose new targets for the copy. If it's a permanent spell, the copy gains haste and "At the beginning of the end step, sacrifice this permanent." (A copy of a permanent spell becomes a token.)

Coercive Recruiter

Whenever this creature or another Pirate you control enters, gain control of target creature until end of turn. Untap that creature. Until end of turn, it gains haste and becomes a Pirate in addition to its other types.

Agent of Treachery

When this creature enters, gain control of target permanent.
At the beginning of your end step, if you control three or more permanents you don't own, draw three cards.

Extraordinary Journey

When this enchantment enters, exile up to X target creatures. For each of those cards, its owner may play it for as long as it remains exiled.
Whenever one or more nontoken creatures enter, if one or more of them entered from exile or was cast from exile, you draw a card. This ability triggers only once each turn.

Don Andres, the Renegade

Each creature you control but don't own gets +2/+2, has menace and deathtouch, and is a Pirate in addition to its other types.
Whenever you cast a noncreature spell you don't own, create two tapped Treasure tokens.

Hoarding Broodlord

Convoke
Flying
When this creature enters, search your library for a card, exile it face down, then shuffle. For as long as that card remains exiled, you may play it.
Spells you cast from exile have convoke.

Wild-Magic Sorcerer

The first spell you cast from exile each turn has cascade. (When you cast your first spell from exile, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)

Nassari, Dean of Expression

At the beginning of your upkeep, exile the top card of each opponent's library. Until end of turn, you may cast spells from among those exiled cards, and you may spend mana as though it were mana of any color to cast those spells.
Whenever you cast a spell from exile, put a +1/+1 counter on Nassari.

Uvilda, Dean of Perfection

{T}: You may exile an instant or sorcery card from your hand and put three hone counters on it. It gains "At the beginning of your upkeep, if this card is exiled, remove a hone counter from it" and "When the last hone counter is removed from this card, if it's exiled, you may cast it. It costs {4} less to cast this way."

Uvilda, Dean of Perfection // Nassari, Dean of Expression

Francisco, Fowl Marauder

Flying
Francisco can't block.
Whenever one or more Pirates you control deal damage to a player, Francisco explores.
Partner (You can have two commanders if both have partner.)

Ramirez DePietro, Pillager

When Ramirez DePietro enters, you lose 2 life and create two Treasure tokens.
Whenever one or more Pirates you control deal combat damage to a player, exile the top card of that player's library. You may cast that card for as long as it remains exiled.

Desertion

Counter target spell. If an artifact or creature spell is countered this way, put that card onto the battlefield under your control instead of into its owner's graveyard.

Forerunner of the Coalition

When this creature enters, you may search your library for a Pirate card, reveal it, then shuffle and put that card on top.
Whenever another Pirate you control enters, each opponent loses 1 life.

Admiral Beckett Brass

Other Pirates you control get +1/+1.
At the beginning of your end step, gain control of target nonland permanent controlled by a player who was dealt combat damage by three or more Pirates this turn.