msem-instigator

{T}, Sacrifice a Treasure, Gold, or permanent named Lotus Petal: Add two mana of any one color.
{T}, Sacrifice a Clue or Omen: Scry 2, then draw a card.
{T}, Sacrifice an Idol: Put two +1/+1 counters on target creature.
{T}, Sacrifice a Food: You gain 6 life.
{T}, Sacrifice a Bullet: Alchemos, Efficiency Engine deals 3 damage to any target.

Haste
Whenever Tailor of Terror attacks, you may exile a creature card from your graveyard. If you do, put a +1/+1 counter on Tailor of Terror.

Enchant player
At the beginning of enchanted player's upkeep, if that player has one or fewer cards in hand, they lose 3 life.

Flying
Ward—{2}, Pay 2 life.
At the beginning of your end step, if a card was put into or left your graveyard this turn, put a +1/+1 counter on Tormentor of Graves.

As an additional cost to cast this spell, sacrifice a permanent.
Sporesowed Disease deals 3 damage to any target and you gain 3 life.

When a creature you control scavenges Harvest Reaper, search your library for a colorless card, reveal it, put it into your hand, then shuffle.
Scavenge {4} ({4}, Exile this card from your graveyard: Put a number of +1/+1 counters equal to this card's power on target creature. Scavenge only as a sorcery.)

As an additional cost to cast this spell, sacrifice a creature.
All creatures get -X/-X until end of turn, where X is the sacrificed creature's power.

Equipped creature gets +1/+1 and has flying.
Equip {2}

When Mouthpiece of Yhzag enters, you may have target opponent create a tapped 1/1 colorless Human creature token.
Whenever Mouthpiece of Yhzag attacks, gain control of target Human creature you don't control with mana value 3 or less until end of turn. Tap it. It's attacking.

Dawn Hill Outskirts enters tapped unless you played it from exile.
{T}: Add {R} or {W}.

Menace (This creature can't be blocked except by two or more creatures.)
Civilized — Whenever Subjugator of Empires attacks, if you control an artifact, a creature, and an enchantment, each opponent discards a card, sacrifices a creature, and loses 3 life.

Artifact spells you cast cost {1} less to cast.
The first ability of an artifact you activate each turn costs {1} less.

Indestructible
Lands you control have “{T}: Add {G}{G}.”
{5}{G}{G}: Double the power and toughness of each creature you control until end of turn.

Rapport — Whenever Grayce Blaen and at least one other creature you control become tapped, scry 1, then reveal the top card of your library. If it's a land card, you may put it onto the battlefield tapped.

Unwavering Questant can't block.
When an opponent fails a trial, return Unwavering Questant from your graveyard to the battlefield.

Menace
Sacrifice a Goblin: Heartless Warleader gets +2/+2 until end of turn.

Pressure {3}{U}{B} (You may cast this spell for its pressure cost if there are seven or more cards in your graveyard.)
Slipstream (This creature can't be blocked as long as only creatures with slipstream are attacking.)
{U}{B}, Reveal Cuxuri Beckoner from your hand: Target player mills two cards.

Exile target spell. Then that card's owner may return it to their hand. If they do, draw a card.

Cards in your hand have lifecycle {3}.
{2}{G}, Sacrifice four creatures: Create two tapped 4/4 green Chimera creature tokens.
Lifecycle {3} ({3}, Discard this card: Create two tapped 1/1 colorless Elemental creature tokens.)

Protection from instants and from sorceries
At the beginning of your upkeep, sacrifice another creature. If you do, put a +1/+1 counter on Andazir, the Crownless.
At the beginning of your end step, if you control four or fewer creatures, transform Andazir.

({T}: Add {W} or {B}.)
Desolate Barrens enters tapped.

Kicker—Return a creature you control to its owner's hand. (You may return a creature you control to its owner's hand in addition to any other costs as you cast this spell.)
Counter target spell. If Shinrei's Ruse was kicked, draw a card.

Trample
Whenever you cycle Long-Term Method Actor or it attacks, proliferate. (Choose any number of permanents and/or players with counters on them, then give each another counter of each kind already there.)
Basic landcycling {1}{G} ({1}{G}, Discard this card: Search your library for a basic land card, reveal it, and put it into your hand, then shuffle.)

Enchant creature
Whenever enchanted creature becomes tapped, Violent Repercussions deals 3 damage to that creature's controller.

Counter target spell unless its controller pays {2}.
Lifecycle {3} ({3}, Discard this card: Create two tapped 1/1 colorless Elemental creature tokens.)