Judge of Currents

Whenever a Merfolk you control becomes tapped, you may gain 1 life.

Hollowsage

Whenever Hollowsage becomes untapped, you may have target player discard a card.

Servant of Tymaret

Inspired — Whenever Servant of Tymaret becomes untapped, each opponent loses 1 life. You gain life equal to the life lost this way.
{2}{B}: Regenerate Servant of Tymaret.

Immersturm Predator

Flying
Whenever Immersturm Predator becomes tapped, exile up to one target card from a graveyard and put a +1/+1 counter on Immersturm Predator.
Sacrifice another creature: Immersturm Predator gains indestructible until end of turn. Tap it.

Stonybrook Schoolmaster

Whenever Stonybrook Schoolmaster becomes tapped, you may create a 1/1 blue Merfolk Wizard creature token.

Veteran of the Depths

Whenever Veteran of the Depths becomes tapped, you may put a +1/+1 counter on it.

Reckless Racer

First strike
Whenever Reckless Racer becomes tapped, you may discard a card. If you do, draw a card.

Siren of the Silent Song

Flying
Inspired — Whenever Siren of the Silent Song becomes untapped, each opponent discards a card, then each opponent mills a card.

Wake Thrasher

Whenever a permanent you control becomes untapped, Wake Thrasher gets +1/+1 until end of turn.

Aerie Worshippers

Inspired — Whenever Aerie Worshippers becomes untapped, you may pay {2}{U}. If you do, create a 2/2 blue Bird enchantment creature token with flying.

Renegade Wheelsmith

Whenever Renegade Wheelsmith becomes tapped, target creature can't block this turn.

Satyr Nyx-Smith

Haste
Inspired — Whenever Satyr Nyx-Smith becomes untapped, you may pay {2}{R}. If you do, create a 3/1 red Elemental enchantment creature token with haste.

Surgespanner

Whenever Surgespanner becomes tapped, you may pay {1}{U}. If you do, return target permanent to its owner's hand.

Felhide Spiritbinder

Inspired — Whenever Felhide Spiritbinder becomes untapped, you may pay {1}{R}. If you do, create a token that's a copy of another target creature, except it's an enchantment in addition to its other types. It gains haste. Exile it at the beginning of the next end step.

Quest for Renewal

Whenever a creature you control becomes tapped, you may put a quest counter on Quest for Renewal.
As long as there are four or more quest counters on Quest for Renewal, untap all creatures you control during each other player's untap step.

Oreskos Sun Guide

Inspired — Whenever Oreskos Sun Guide becomes untapped, you gain 2 life.

Fallowsage

Whenever Fallowsage becomes tapped, you may draw a card.

Disciple of Deceit

Inspired — Whenever Disciple of Deceit becomes untapped, you may discard a nonland card. If you do, search your library for a card with the same mana value as that card, reveal it, put it into your hand, then shuffle.

Arbiter of the Ideal

Flying
Inspired — Whenever Arbiter of the Ideal becomes untapped, reveal the top card of your library. If it's an artifact, creature, or land card, you may put it onto the battlefield with a manifestation counter on it. That permanent is an enchantment in addition to its other types.

Ghostly Pilferer

Whenever Ghostly Pilferer becomes untapped, you may pay {2}. If you do, draw a card.
Whenever an opponent casts a spell from anywhere other than their hand, draw a card.
Discard a card: Ghostly Pilferer can't be blocked this turn.

Emmara, Soul of the Accord

Whenever Emmara, Soul of the Accord becomes tapped, create a 1/1 white Soldier creature token with lifelink.

God-Favored General

Inspired — Whenever God-Favored General becomes untapped, you may pay {2}{W}. If you do, create two 1/1 white Soldier enchantment creature tokens.

Pain Seer

Inspired — Whenever Pain Seer becomes untapped, reveal the top card of your library and put that card into your hand. You lose life equal to that card's mana value.

Magda, Brazen Outlaw

Other Dwarves you control get +1/+0.
Whenever a Dwarf you control becomes tapped, create a Treasure token.
Sacrifice five Treasures: Search your library for an artifact or Dragon card, put that card onto the battlefield, then shuffle.

Sphinx's Disciple

Flying
Inspired — Whenever Sphinx's Disciple becomes untapped, draw a card.

King Macar, the Gold-Cursed

Inspired — Whenever King Macar, the Gold-Cursed becomes untapped, you may exile target creature. If you do, create a Gold token. (It's an artifact with "Sacrifice this artifact: Add one mana of any color.")