msem-instigator

At the beginning of combat on your turn, choose a permanent type at random. Each player sacrifices a permanent of the chosen type other than this enchantment. If no permanents were sacrificed this way, sacrifice this enchantment and create a 6/6 black and red Rat Mutant creature token with trample and haste.

Whenever one or more other creatures you control deal combat damage to an opponent, choose one —
• That player discards a card at random.
• That player sacrifices a creature with toughness 4 or less.

Starting with you, each player either passes or reveals the top card of their library. Each player that revealed a card this way pays life equal to its mana value. If a player can't, that player passes. Then each player who hasn't passed yet puts that card into their hand. Repeat this process until each player has passed.

Whenever a creature enters, each opponent loses 1 life.

Destroy target creature.

{2}, Sacrifice a creature or Rewards of Ruthlessness: Creatures you control get +1/+0 until end of turn.

Archive 5 (As this enters, shuffle the top five cards of your main library into a new face up library. Sacrifice this after the archived library is empty.)
You may play legendary cards from the top of the archived library.

[+1]: Reveal the top card of your library and put it into your hand. Then if that card wasn't legendary, discard a card.
[–X]: Return target non-Reyhsia legendary permanent card with mana value X from your graveyard to the battlefield.
[–6]: Reyhsia, the Honorless deals 4 damage to each nonlegendary creature.

Flying, haste
Whenever Rhyolithic Hellkite attacks, you may sacrifice a land or exile a land card from your graveyard. If you do, put a +1/+1 counter on Rhyolithic Hellkite.

Choose one —
• Destroy target monocolored creature.
• Ria-Demian Charm deals 2 damage to each creature.
• Each player discards two cards and loses 2 life.

Destroy target creature. Creatures without flying can't block this turn.

Sammel Wyldjack enters with a fuse counter on him.
At the beginning of your upkeep, remove a fuse counter from Sammel Wyldjack. If you do, each player sacrifices four lands and Sammel Wyldjack deals 4 damage to each other creature.

Whenever Scathing Critics deals combat damage to a player or planeswalker, put a +1/+1 counter on it.

Disgraced 1 (This enters with a -1/-1 counter. Whenever it deals combat damage to a player, remove all -1/-1 counters from it.)
Whenever you put one or more -1/-1 counters on Scion of Fiends or another creature, Scion of Fiends deals that much damage to each opponent.

Enchant creature
Enchanted creature gets +2/-2.

Wither (This deals damage to creatures in the form of -1/-1 counters.)
Whenever a creature with wither deals combat damage to an opponent, Scorchmark Seer deals 2 damage to that player.

This spell costs {2} less to cast for each creature that died this turn.
Each player exiles all creature cards from their graveyard, then sacrifices each creature they control, then puts all creature cards they own exiled this way onto the battlefield. Exile Sea of Corpses.

When Shala Na enters, each player chooses a creature they control, then sacrifices the rest.
[+1]: Up to one target creature you control gains double strike and haste until end of turn.
[–6]: You get an emblem with “Whenever a creature dies, each opponent loses 2 life.”

Haste
Whenever Shala's Phantasm attacks, you may sacrifice a creature. If you do, Shala's Phantasm deals 3 damage to any target.

When Shaman of Burning Ashes enters, return target instant or sorcery card from your graveyard to your hand. When you do, each opponent loses X life, where X is that card's mana value.

Choose two —
• Target creature gets +2/+0 until end of turn.
• Two target creatures can't block this turn.
• Target player discards two cards, then draws a card for each card they discarded this way.
• Shi Hou's Command deals 4 damage to target legendary creature or planeswalker.

Transcend (Activate as a sorcery to gain the next type and a +1/+1 counter.)
Ward—Discard a card.
{B}{R}: Demigod — Draw a card, then discard a card. You may have each opponent sacrifice a nonland permanent with the same mana value as the discarded card.
{4}{B}{R}: God — Create two tokens that are copies of Shi Hou's back face.

Whenever you discard one or more cards, create a Treasure token and draw a card. This ability triggers only once each turn.
Whenever two or more creatures you control attack, you may discard a card. If you do, target creature can't block this turn.

Whenever you attack, each opponent loses 3 life unless they discard a card or sacrifice a nonland permanent. Repeat this process once.
Fleeting {B}{R} (You may cast this spell for its fleeting cost. If you do, sacrifice it at the beginning of the next end step.)

Whenever Slyten Connoisseur attacks, crystallize. (Put a +1/+1 counter on a creature you control or create a Treasure.)
Once each turn, when an artifact you control dies, you may pay 1 life. If you do, draw a card.