msem-instigator

When Twice-Lived Dead dies, create a 2/2 black Zombie creature token.

Flying, haste
Whenever another creature dies, Twinfire Dragon gets +1/+0 until end of turn.

Hexproof
Whenever Twinning Psionic harnesses an instant or sorcery spell, you may copy that spell. If you do, you may choose new targets for the copy.

{1}, Sacrifice another creature: Crystallize. Activate only as a sorcery. (Put a +1/+1 counter on a creature you control or create a Treasure.)
{W}{U}{B}{R}{G}: Target creature gets +3/+3 and gains trample until end of turn. Activate only as a sorcery.

Flying
Ward—Pay 4 life. (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays 4 life.)
Whenever you cast an instant spell, draw a card.
Whenever you cast a sorcery spell, Typhoon Terror deals 2 damage to any target.

This spell costs {1} less to cast for each foretold card you own in exile, each permanent you control with foretell, and each card with foretell in your graveyard.
Flying
When Tyrant of Prophecies enters the battlefield, it deals 3 damage to any target.

Trample, haste
When Tyrants of Bundan enters the battlefield, tap all lands target player controls. They don't untap during their controller's next untap step.

Flying, vigilance
When Tyriel, Angelic Artisan enters the battlefield, you may search your library for an Equipment card, reveal it, put it into your hand, then shuffle.
Whenever Tyriel attacks, you may put an Equipment card from your hand onto the battlefield, then attach it to Tyriel.

This spell costs {1} less to cast for each Scarecrow you control.
Other creatures you control get +0/+2 and have vigilance.

Other Hounds you control have trample.
{R/W}, {T}: Put a +1/+1 counter on target Hound you control.

{2/B}: Umbral Stalker gains indestructible until end of turn. Tap it.

Resolute — Umbral Wolf can't be blocked by more than one creature as long as Umbral Wolf's power is greater than its base power.

Assault {X}{R}{R} (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.)
Other Elementals you control get +1/+0.
When Unbound Annihilus assaults, create X 1/1 red Elemental creature tokens that are tapped and attacking.

Whenever you cast another creature spell, create a 1/1 green and white Elk Spirit creature token.
As long as you control five or more Elk, creatures you control get +3/+3 and have trample.

Hexproof
When Uncharted Leviathan enters the battlefield, target creature can't be blocked this turn.

Enspirit (As you cast this spell, you may exile a nonenchantment creature you control until this leaves the battlefield or fails to resolve. Reduce this spell's cost by the exiled card's mana value.)
Deathtouch

When Undead Banneret enters the battlefield, if you control a legendary creature, each opponent loses 4 life.

This spell costs {1} less to cast for each Zombie creature card in your graveyard.
When Undead Harbinger enters the battlefield, return target Zombie card from your graveyard to your hand.

Mark (Whenever this creature attacks, mark target creature until end of turn.)
Undercity Diplomat can't be blocked by marked creatures.

When Undying Lich dies, create a 6/3 black Zombie Horror creature token with menace and “When this creature dies, create an 8/5 black Elder Demon Horror creature token with flying, deathtouch, and menace.”

Flying, vigilance
When you attain Unfallen Angel, target opponent discards a card.

Flying
When Unfettered Atrocity enters the battlefield, destroy target creature or planeswalker.

Add X mana in any combination of colors, where X is the amount of mana spent to cast Unravel Shattered Worlds.
Coalesce {7} (You may cast this from your graveyard for {7}. If you do, put it onto the battlefield as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)

Unreflected Cultist can't be blocked by Reflections.