Ephara's Enlightenment

Enchant creature
When this Aura enters, put a +1/+1 counter on enchanted creature.
Enchanted creature has flying.
Whenever a creature you control enters, you may return this Aura to its owner's hand.

Ordeal of Thassa

Enchant creature
Whenever enchanted creature attacks, put a +1/+1 counter on it. Then if it has three or more +1/+1 counters on it, sacrifice this Aura.
When you sacrifice this Aura, draw two cards.

Blessed Spirits

Flying
Whenever you cast an enchantment spell, put a +1/+1 counter on this creature.

War-Wing Siren

Flying
Heroic — Whenever you cast a spell that targets this creature, put a +1/+1 counter on this creature.

Hinata, Dawn-Crowned

Flying, trample
Spells you cast cost {1} less to cast for each target.
Spells your opponents cast cost {1} more to cast for each target.

Sheriff of Safe Passage

This creature enters with a +1/+1 counter on it plus an additional +1/+1 counter on it for each other creature you control.
Plot {1}{W} (You may pay {1}{W} and exile this card from your hand. Cast it as a sorcery on a later turn without paying its mana cost. Plot only as a sorcery.)

Illvoi Operative

Whenever you cast your second spell each turn, put a +1/+1 counter on this creature.

Patrolling Peacemaker

This creature enters with two +1/+1 counters on it.
Whenever an opponent commits a crime, proliferate. (They commit a crime if they target an opponent, anything an opponent controls, and/or cards in an opponent's graveyard. To proliferate, you choose any number of permanents and/or players, then give each another counter of each kind already there.)

Erudite Wizard

Whenever you draw your second card each turn, put a +1/+1 counter on this creature.

Fiend Hunter

When this creature enters, you may exile another target creature.
When this creature leaves the battlefield, return the exiled card to the battlefield under its owner's control.

Hero of Iroas

Aura spells you cast cost {1} less to cast.
Heroic — Whenever you cast a spell that targets this creature, put a +1/+1 counter on this creature.

Cosmogrand Zenith

Whenever you cast your second spell each turn, choose one —
• Create two 1/1 white Human Soldier creature tokens.
• Put a +1/+1 counter on each creature you control.

Clarion Conqueror

Flying
Activated abilities of artifacts, creatures, and planeswalkers can't be activated.

Hero of the Pride

Whenever you cast a spell that targets this creature, creatures you control get +1/+0 until end of turn.

Triton Fortune Hunter

Heroic — Whenever you cast a spell that targets this creature, draw a card.

Emberheart Challenger

Haste
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Valiant — Whenever this creature becomes the target of a spell or ability you control for the first time each turn, exile the top card of your library. Until end of turn, you may play that card.

Battlewise Hoplite

Heroic — Whenever you cast a spell that targets this creature, put a +1/+1 counter on this creature, then scry 1. (To scry 1, look at the top card of your library, then you may put that card on the bottom.)

Stormchaser Drake

Flying
Whenever this creature becomes the target of a spell you control, draw a card.

Razzle-Dazzler

Whenever you cast your second spell each turn, put a +1/+1 counter on this creature. It can't be blocked this turn.

Mesa Enchantress

Whenever you cast an enchantment spell, you may draw a card.

Champion of the Parish

Whenever another Human you control enters, put a +1/+1 counter on this creature.

Entity Tracker

Flash
Eerie — Whenever an enchantment you control enters and whenever you fully unlock a Room, draw a card.

Wavecrash Triton

Heroic — Whenever you cast a spell that targets this creature, tap target creature an opponent controls. That creature doesn't untap during its controller's next untap step.

Whiskervale Forerunner

Valiant — Whenever this creature becomes the target of a spell or ability you control for the first time each turn, look at the top five cards of your library. You may reveal a creature card with mana value 3 or less from among them. You may put it onto the battlefield if it's your turn. If you don't put it onto the battlefield, put it into your hand. Put the rest on the bottom of your library in a random order.

Pearl-Ear, Imperial Advisor

Lifelink
Enchantment spells you cast have affinity for Auras. (They cost {1} less to cast for each Aura you control.)
Whenever you cast an Aura spell that targets a modified permanent you control, draw a card. (Equipment, Auras you control, and counters are modifications.)

Light of Promise

Enchant creature
Enchanted creature has "Whenever you gain life, put that many +1/+1 counters on this creature."

Hero of the Games

Brigone, Soldier of Meletis

Vigilance
Heroic — Whenever you cast a spell that targets Brigone, put a +1/+1 counter on Brigone.
{T}, Remove a +1/+1 counter from Brigone: Draw a card.

Fabled Hero

Double strike
Heroic — Whenever you cast a spell that targets this creature, put a +1/+1 counter on it.

Phalanx Leader

Heroic — Whenever you cast a spell that targets this creature, put a +1/+1 counter on each creature you control.

Lagonna-Band Trailblazer

Heroic — Whenever you cast a spell that targets this creature, put a +1/+1 counter on it.

Gleam of Authority

Enchant creature
Enchanted creature gets +1/+1 for each +1/+1 counter on other creatures you control.
Enchanted creature has vigilance and "{W}, {T}: Bolster 1." (To bolster 1, choose a creature with the least toughness among creatures you control and put a +1/+1 counter on it.)

Favored Hoplite

Heroic — Whenever you cast a spell that targets this creature, put a +1/+1 counter on this creature and prevent all damage that would be dealt to it this turn.

Banisher Priest

When this creature enters, exile target creature an opponent controls until this creature leaves the battlefield.

Arna Kennerüd, Skycaptain

Flying, lifelink
Ward—Discard a card.
Whenever a modified creature you control attacks, double the number of each kind of counter on it. Then for each nontoken permanent attached to it, create a token that's a copy of that permanent attached to that creature.

Agent of the Fates

Deathtouch
Heroic — Whenever you cast a spell that targets this creature, each opponent sacrifices a creature of their choice.

Bloodsky Berserker

Whenever you cast your second spell each turn, put two +1/+1 counters on this creature. It gains menace until end of turn. (It can't be blocked except by two or more creatures.)

Meletis Astronomer

Heroic — Whenever you cast a spell that targets this creature, look at the top three cards of your library. You may reveal an enchantment card from among them and put it into your hand. Put the rest on the bottom of your library in any order.

Eternal Thirst

Enchant creature
Enchanted creature has lifelink and "Whenever a creature an opponent controls dies, put a +1/+1 counter on this creature." (Damage dealt by a creature with lifelink also causes its controller to gain that much life.)

Akroan Skyguard

Wingsteed Rider

Heartfire Hero

Valiant — Whenever this creature becomes the target of a spell or ability you control for the first time each turn, put a +1/+1 counter on it.
When this creature dies, it deals damage equal to its power to each opponent.

Skyknight Squire

Whenever another creature you control enters, put a +1/+1 counter on this creature.
As long as this creature has three or more +1/+1 counters on it, it has flying and is a Knight in addition to its other types.

Hero of the Nyxborn

When this creature enters, create a 1/1 white Human Soldier creature token.
Whenever you cast a spell that targets this creature, creatures you control get +1/+0 until end of turn.

Bloodcrazed Hoplite

Heroic — Whenever you cast a spell that targets this creature, put a +1/+1 counter on it.
Whenever a +1/+1 counter is put on this creature, remove a +1/+1 counter from target creature an opponent controls.

Glyph Elemental

Bestow {1}{W} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached.)
Landfall — Whenever a land you control enters, put a +1/+1 counter on this permanent.
Enchanted creature gets +1/+1 for each +1/+1 counter on this Aura.

Cliffside Rescuer

Vigilance
{T}, Sacrifice this creature: Target permanent you control gains protection from each of your opponents until end of turn. (It can't be blocked, targeted, dealt damage, enchanted, or equipped by anything controlled by those players.)

Dreamtide Whale

Vanishing 2 (This creature enters with two time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
Whenever a player casts their second spell each turn, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)