Dire Fleet Warmonger

At the beginning of combat on your turn, you may sacrifice another creature. If you do, Dire Fleet Warmonger gets +2/+2 and gains trample until end of turn. (It can deal excess combat damage to the player or planeswalker it's attacking.)

Ruthless Knave

{2}{B}, Sacrifice a creature: Create two Treasure tokens. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")
Sacrifice three Treasures: Draw a card.

Angrath's Ambusher

Angrath's Ambusher gets +2/+0 as long as you control an Angrath planeswalker.

Devoted Paladin

Beacon of Hope — When Devoted Paladin enters the battlefield, creatures you control get +1/+1 and gain vigilance until end of turn.

Guild Thief

Whenever Guild Thief deals combat damage to a player, put a +1/+1 counter on it.
Cunning Action — {3}{U}: Guild Thief can't be blocked this turn.

Storm Fleet Arsonist

Raid — When Storm Fleet Arsonist enters the battlefield, if you attacked this turn, target opponent sacrifices a permanent.

Elemental Expressionist

Magecraft — Whenever you cast or copy an instant or sorcery spell, choose target creature you control. Until end of turn, it gains "If this creature would leave the battlefield, exile it instead of putting it anywhere else" and "When this creature is put into exile, create a 4/4 blue and red Elemental creature token." (Each instance of that ability triggers separately.)

Gruesome Scourger

When Gruesome Scourger enters the battlefield, it deals damage to target opponent or planeswalker equal to the number of creatures you control.

Argivian Cavalier

Enlist (As this creature attacks, you may tap a nonattacking creature you control without summoning sickness. When you do, add its power to this creature's until end of turn.)
When Argivian Cavalier enters the battlefield, create a 1/1 white Soldier creature token.

Prismari Pledgemage

Defender
Magecraft — Whenever you cast or copy an instant or sorcery spell, Prismari Pledgemage can attack this turn as though it didn't have defender.

Tymora's Invoker

Dire Fleet Ravager

Menace, deathtouch
When Dire Fleet Ravager enters the battlefield, each player loses a third of their life, rounded up.

Augusta, Dean of Order

Other tapped creatures you control get +1/+0.
Other untapped creatures you control get +0/+1.
Whenever you attack, untap each creature you control, then tap any number of creatures you control.

Plargg, Dean of Chaos

{T}, Discard a card: Draw a card.
{4}{R}, {T}: Reveal cards from the top of your library until you reveal a nonlegendary, nonland card with mana value 3 or less. You may cast that card without paying its mana cost. Put all revealed cards not cast this way on the bottom of your library in a random order.

Plargg, Dean of Chaos // Augusta, Dean of Order

Orcish Vandal

{T}, Sacrifice an artifact: Orcish Vandal deals 2 damage to any target.

Intrepid Outlander

Reach
Pack tactics — Whenever Intrepid Outlander attacks, if you attacked with creatures with total power 6 or greater this combat, venture into the dungeon. (Enter the first room or advance to the next room.)

Dire Fleet Captain

Whenever Dire Fleet Captain attacks, it gets +1/+1 until end of turn for each other attacking Pirate.

Rootha, Mercurial Artist

{2}, Return Rootha, Mercurial Artist to its owner's hand: Copy target instant or sorcery spell you control. You may choose new targets for the copy.

Ruin Raider

Raid — At the beginning of your end step, if you attacked this turn, reveal the top card of your library and put that card into your hand. You lose life equal to the card's mana value.

Headstrong Brute

Headstrong Brute can't block.
Headstrong Brute has menace as long as you control another Pirate.

Fathom Fleet Boarder

When Fathom Fleet Boarder enters the battlefield, you lose 2 life unless you control another Pirate.

Vengeful Warchief

Whenever you lose life for the first time each turn, put a +1/+1 counter on Vengeful Warchief. (Damage causes loss of life.)