msem-instigator

Choose one —
• Forge Trick deals 3 damage to target creature.
• Target creature gets +3/+0 until end of turn.

First strike, haste
Whenever Soulflare Nymph deals damage to a creature, exile that creature.

Draw two cards, then you may foretell a card with foretell from your hand. It costs {0} to foretell this way. You lose 2 life. (You don't reveal that card. You can't foretell cards without foretell in this way.)

I, II, III — Target creature gets -X/-X until end of turn, where X is the number of lore counters on A Grave Sentence.
IV — Target opponent loses 1 life for each creature card in their graveyard.
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Discard a land card: Draw a card. Shardstorm Elemental gets +1/+0 and gains flying until end of turn. Activate only once each turn.

Equipped creature gets +2/+2 and has reach and protection from enchantment creatures. (It can't be blocked, targeted, or dealt damage by enchantment creatures.)
Equip {3}

Deathtouch

Exile target creature, then exile target creature card from a graveyard. An opponent chooses one of them. Put the chosen card onto the battlefield under your control.

University Archive enters tapped.
When University Archive enters, look at the top card of your library. You may put it into your graveyard.
{T}: Add {U} or {R}.

Whenever Wandering Conqueror attacks, it explores. (Reveal the top card of your library. Put it into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then you may put that card in your graveyard.)
As Wandering Conqueror explores a land, you may put that card into your graveyard. Whenever you do, Wandering Conqueror deals 2 damage to target player or planeswalker.

Whenever an attacking creature dies, you may pay {R}. If you do, create a 2/1 red Merfolk creature token.

When Frantic Efreetspeaker enters, you may discard a card. If you do, draw a card.
{2}, Exile Frantic Efreetspeaker from your graveyard: Create a Treasure token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color.”)

Golden age (If you cast an instant or sorcery spell, activated a nonmana ability, and attacked this turn, enter a renaissance for this game.)
Whenever a Demon you control enters, put a +1/+1 counter on Tzelin.
{2}{B}: Sacrifice Tzelin. If you do, each opponent loses life equal to Tzelin's power. If you're in a renaissance, also draw that many cards.

Revive—{B}, Discard a card. ({B}, Discard a card, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

This spell costs {1} less to cast for each creature type among creatures you control.
Return up to two target cards from your graveyard to your hand. Exile Intersection of Fates.

As an additional cost to cast this spell, put two -1/-1 counters on a creature you control.
Draw two cards.

When Bird Call enters, search your library for a creature card, reveal it, shuffle, then put that card on top.
{2}, {T}: Target creature gets +1/+1 until end of turn.

Whenever Zealous Scaleblight becomes tapped, it deals 1 damage to any target.

Target creature you control deals damage equal to its power to target creature you don't control. If the creature you control is legendary, excess damage is dealt to that creature's controller instead.

At the beginning of your end step, if there are three or more creature cards in your graveyard, put a +1/+1 counter on target creature you control.

Flash
Flying, protection from sorceries
You may look at the top card of your library any time.
You may cast spells from the top of your library as long as it's not your main phase.

As long as it's your turn, Seto San is a 3/3 Human Warrior creature with indestructible.
[+1]: Up to one target creature you control gains lifelink until end of turn.
[0]: Create a 1/1 white Warrior creature token.
[–X]: Search your library for an Aura or Equipment card with mana value X and put it onto the battlefield, then shuffle.

You gain 5 life. Investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)
Flashback {2}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Whenever Gifted Warmage attacks, upgrade it. (Give it one of the listed counters it doesn't already have.)
• +1/+1
• Flying