Undergrowth Champion

If damage would be dealt to Undergrowth Champion while it has a +1/+1 counter on it, prevent that damage and remove a +1/+1 counter from Undergrowth Champion.
Landfall — Whenever a land you control enters, put a +1/+1 counter on Undergrowth Champion.

Mossborn Hydra

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
This creature enters with a +1/+1 counter on it.
Landfall — Whenever a land you control enters, double the number of +1/+1 counters on this creature.

Koma, World-Eater

This spell can't be countered.
Trample, ward {4}
Whenever Koma deals combat damage to a player, create four 3/3 blue Serpent creature tokens named Koma's Coil.

Scrawling Crawler

At the beginning of your upkeep, each player draws a card.
Whenever an opponent draws a card, that player loses 1 life.

Kykar, Zephyr Awakener

Flying
Whenever you cast a noncreature spell, choose one —
• Exile another target creature you control. Return that card to the battlefield under its owner's control at the beginning of the next end step.
• Create a 1/1 white Spirit creature token with flying.

Giada, Font of Hope

Flying, vigilance
Each other Angel you control enters with an additional +1/+1 counter on it for each Angel you already control.
{T}: Add {W}. Spend this mana only to cast an Angel spell.

Eidolon of Astral Winds

Vigilance
Constellation — Whenever Eidolon of Astral Winds or another enchantment you control enters, choose target creature you control. Until end of turn, that creature has base power and toughness 4/4 and gains flying.

Exemplar of Light

Flying
Whenever you gain life, put a +1/+1 counter on this creature.
Whenever you put one or more +1/+1 counters on this creature, draw a card. This ability triggers only once each turn.

Infernal Vessel

When this creature dies, if it wasn't a Demon, return it to the battlefield under its owner's control with two +1/+1 counters on it. It's a Demon in addition to its other types.

Go Forth

Choose one—
• Search your library for a basic land card, reveal it, put it into your hand, then shuffle.
• Target creature gets +2/+2 until end of turn.

Fumulus, the Infestation

Flying, deathtouch
Whenever a player sacrifices a nontoken creature, create a 1/1 black Insect creature token with flying.
Whenever an Insect, Leech, Slug, or Worm you control attacks, defending player loses 1 life and you gain 1 life.

Adeline, Resplendent Cathar

Vigilance
Adeline, Resplendent Cathar's power is equal to the number of creatures you control.
Whenever you attack, for each opponent, create a 1/1 white Human creature token that's tapped and attacking that player or a planeswalker they control.

Dazzling Angel

Flying
Whenever another creature you control enters, you gain 1 life.

Temporal Manipulation

Brimaz, King of Oreskos

Vigilance
Whenever Brimaz, King of Oreskos attacks, create a 1/1 white Cat Soldier creature token with vigilance that's attacking.
Whenever Brimaz blocks a creature, create a 1/1 white Cat Soldier creature token with vigilance that's blocking that creature.

Banner of Kinship

As this artifact enters, choose a creature type. This artifact enters with a fellowship counter on it for each creature you control of the chosen type.
Creatures you control of the chosen type get +1/+1 for each fellowship counter on this artifact.

Electroduplicate

Create a token that's a copy of target creature you control, except it has haste and "At the beginning of the end step, sacrifice this token."
Flashback {2}{R}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Raise the Past

Return all creature cards with mana value 2 or less from your graveyard to the battlefield.

Lord of the Unreal

Illusion creatures you control get +1/+1 and have hexproof. (They can't be the targets of spells or abilities your opponents control.)

Ajani, Adversary of Tyrants

+1: Put a +1/+1 counter on each of up to two target creatures.
−2: Return target creature card with mana value 2 or less from your graveyard to the battlefield.
−7: You get an emblem with "At the beginning of your end step, create three 1/1 white Cat creature tokens with lifelink."

Zimone, Paradox Sculptor

At the beginning of combat on your turn, put a +1/+1 counter on each of up to two target creatures you control.
{G}{U}, {T}: Double the number of each kind of counter on up to two target creatures and/or artifacts you control.

Generous Pup

Vigilance
Whenever one or more +1/+1 counters are put on Generous Pup, put a +1/+1 counter on each other creature you control. This ability triggers only once each turn.

Frontline Heroism

When Frontline Heroism enters, create a 1/1 red Soldier creature token with haste.
Whenever you cast a spell that targets only a single creature you control, create a 1/1 red Soldier creature token with haste, then copy that spell. The copy targets that token.

Alesha, Who Laughs at Fate

First strike
Whenever Alesha attacks, put a +1/+1 counter on it.
Raid — At the beginning of your end step, if you attacked this turn, return target creature card with mana value less than or equal to Alesha's power from your graveyard to the battlefield.

Herald of Eternal Dawn

Flash (You may cast this spell any time you could cast an instant.)
Flying
You can't lose the game and your opponents can't win the game.