msem-instigator

Target player reveals their hand. You choose a nonland card from it. That player discards that card.

Whenever Eclipse Knight attacks, each opponent loses 1 life. You gain life equal to the life lost this way.
Eclipse Knight gets +1/+1 as long as you have 10 or more life than your starting life total.
Eclipse Knight gets +1/+1 as long as an opponent has 10 or less life than their starting life total.

Whenever you cast an artifact or enchantment spell, scry 1, then create a 1/1 white Merfolk creature token.
Whenever you cast a Merfolk spell, look at the top card of your library. If it's an artifact or enchantment card, you may reveal it and put it into your hand.

Whenever one or more creatures you control deal combat damage to a player or planeswalker, create a Clue token.
{G}{U}, Sacrifice a Clue: Put a +1/+1 counter on target creature. Proliferate.

The next creature spell you cast this turn can be cast as though it had flash. When that creature enters the battlefield this turn, it gains lifelink until end of turn.

{1}{R}, {T}, Sacrifice an artifact: Elise, Maktali Prodigy deals 2 damage to any target.
{1}{U}, {T}, Sacrifice an artifact: Return target nonland permanent to its owner's hand.
{3}{U}{R}, {T}, Sacrifice three artifacts: Discard your hand, then draw seven cards.

Defender, reach
{T}, Discard a card: Create a 0/2 red and green Scarecrow creature token with defender and reach.
{R}{G}, {T}: Embergourd Scarecrow deals X damage to target player or planeswalker, where X is the number of creatures with defender you control.

Gestalt (When this or another creature enters under your control, you may merge it with the one in play, keeping counters and attachments. They become the permanent on top plus all abilities from under it.)
When this creature dies, it deals X damage to target player or planeswalker, where X is the number of cards and tokens merged with it.

Trample
Assault {2}{R}{G} (Whenever this attacks, if it has no +1/+1 counters on it, you may pay its assault cost to put a +1/+1 counter on it.)
If one or more +1/+1 counters would be put on a creature you control, that many plus one +1/+1 counters are put on it instead.

Destroy target creature.

Flying, vigilance
Embattled creatures you control have ward {1}.
Whenever one or more creatures you control deal combat damage to a player, put a +1/+1 counter on one of those creatures.

Enchant creature
When Ethereal Fervor enters the battlefield, adjudicate. (Create a white Aura enchantment token with enchant creature and “Sacrifice this token: Untap enchanted creature” attached to target creature.)
Enchanted creature gets +1/+0 for each Aura attached to it, has first strike, and attacks each combat if able.

Reveal the top two cards of your library. Put up to one land card and up to one nonland card from among them into your hand. Put the rest on the bottom in any order.

{1}, {T}, Exile a land card from your graveyard: Add two mana in any combination of colors.
{B}{G}, {T}, Discard a card: Nourish 2. (To nourish 2, either put two +1/+1 counters on this creature or create two 1/1 white Citizen creature tokens.)

Up to one target creature can't block this turn. (Then exile this card. You may play the land later from exile.)

Fahrib Informant can't be blocked by creatures with greater power.
Whenever one or more creatures you control deal damage to an opponent, put a +1/+1 counter on Fahrib Informant.

Target opponent discards a card. If they can't, draw a card. (Then exile this card. You may cast the creature later from exile.)

First strike
Sacrifice Fearless General: Soldiers you control gain indestructible until end of turn.

Choose one—
• Fellor Charm deals 3 damage to any target.
• Target creature gains lifelink and indestructible until end of turn.
• Attacking creatures get +1/+1 until end of turn.

Whenever a creature you control dies, put a rot counter on Fester Swarm and you gain 1 life.
{B}{G}, Remove two or more rot counters from Fester Swarm: Create a 1/1 green Insect creature token, then put a +1/+1 counter on it for each rot counter removed this way.

Exile the top card of your library. You may cast it. (Then exile this card. You may play the land later from exile.)

Vanishing 2 (This permanent enters the battlefield 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 discards one or more cards, put a time counter on Fleeting Moments.
Whenever a time counter is removed from Fleeting Moments, you draw a card and you lose 1 life.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
{U}{R}, Exile an instant or sorcery card from your graveyard: Foolhardy Huo gains flying and first strike until end of turn.

At the beginning of each combat, prevent all combat damage that would be dealt to and dealt by up to one target creature this turn.
{X}{G}{U}, Sacrifice Foreboding Calm: Create an X/X green and blue Plant Horror creature token with hexproof and trample.

{B}{R}, Sacrifice a creature: Create a token that's a copy of Forlorn Companion, except it has no mana cost.