msem-instigator

Whenever a spell or ability causes an opponent to draw a card, draw a card unless that player pays 1 life.

Flying
When Endmire Raven dies, each opponent loses 2 life and you gain 2 life.

First strike
When Engulfing Incubus enters, you may submerge target nontoken creature an opponent controls. When Engulfing Incubus is no longer on the battlefield, turn that card face up. (To submerge a card, exile it, then put it on the battlefield face down under its owner's control as a 2/2 creature.)

Whenever another creature dies, upgrade Entitled Griefer. (Give it one of the listed counters it doesn't already have.)
• +1/+1
• Deathtouch
• Lifelink

Eternal Duneborn enters tapped.
Foresight — Whenever you draw your second card each turn, return Eternal Duneborn from your graveyard to your hand.

Once during each of your turns, when you sacrifice a permanent, you may have target opponent lose 3 life unless they sacrifice a nonland permanent or discard a card.

Lifelink

Flying
Assault {2}{B} (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.)
When Harbinger of Locusts assaults, you may search your library for an Insect card, reveal it, put it into your hand, then shuffle.

When Harvest Blighter enters, create a black Aura Curse enchantment token named Rotting Away attached to target player. The token has enchant player and “Whenever a creature enters under enchanted player's control, if it has toughness 2 or greater, put a -1/-1 counter on that creature.”

Flying
Whenever Haunting Horseman deals combat damage to a player, that player discards a card.

Lifelink
Embellish {2}{B} (If you cast this spell for {2}{B}, create a 1/1 blue Thopter artifact creature token with flying when it enters.)

Lifelink

At the beginning of your upkeep, if you control a legendary creature, you draw a card and you lose 1 life.

Voracious 2 (As this enters, you may sacrifice up to two artifacts and/or creatures. This creature enters with that many +1/+1 counters on it.)
When Hunted Wolf enters, create a 2/2 black Soldier creature token.

Menace
When Icilica's Icestrider enters, choose one —
• Draw a card if you own a card in exile.
• Target player discards a card if that player owns a card in exile.

Flash
Whenever Iken Company Nightwalker deals combat damage to a player, put a +1/+1 counter on it.

Civilized — At the beginning of your upkeep, if you control an artifact, a creature, and an enchantment, you draw a card and you lose 1 life.

When Killdrone Engineer enters, create a 1/1 colorless Servo artifact creature token.
Artifacts you control have deathtouch.

Revive {3}{B} ({3}{B}, 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.)

When Leech-Ridden Corpse dies, each opponent loses 1 life and you gain 1 life.

Whenever a +1/+1 counter is put on Lifeblood Leecher, target creature an opponent controls gets -1/-1 until end of turn.

{2}{B}, Exile Lizhao's Soulblade from your graveyard: Return target creature card from your graveyard to your hand. Activate only as a sorcery.

Transcend (Activate as a sorcery to gain the next type and a +1/+1 counter.)
Lifelink
Demon spells you cast cost {B} less to cast and an additional 2 life to cast.
{3}{B/R}{B/R}: Demon
Discard your hand. Draw a number of cards equal to the greatest power among Demons you control.
{5}{U/B}{U/B}: Noble
Gain control of target creature. You lose life equal to its mana value.

Whenever Luna enters or phases in, each player loses 1 life.
Whenever a player casts a spell or a creature attacks, Luna phases out.