msem-instigator

Riv's Safehouse enters tapped.
When Riv's Safehouse enters, you may mill two cards.
{T}: Add {U} or {B}.

Flying
When Emissary of the Wicked enters, you lose 4 life.
Revive {2}{B}{B} ({2}{B}{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 Battlefield Tiger enters, create two 1/1 white Soldier creature tokens.

{3}, {T}: Put a +1/+1 counter on target creature. This ability costs {3} less to activate if you've sacrificed a permanent this turn. Active only as a sorcery.

Whenever an enchantment you control enters, target opponent loses 1 life and you gain 1 life.

Whenever a creature you control deals combat damage to a player, it cackles. (Put a menace counter on it. If it already has menace, it deals 1 damage to each opponent instead.)
{3}{B}: Each creature you control with menace gains lifelink until end of turn.

Flash
Prowess
When High Rollers Esteemed enters, you may choose new targets for target spell or ability unless its controller has High Rollers Esteemed deal 4 damage to them.

When Greypelt Clergy enters, choose one —
• Put a +1/+1 counter on Greypelt Clergy.
• Permutate. (You may remove a counter from a creature you control. If you do, put two +1/+1 counters on a different creature you control.)

This spell costs {2} less to cast if you control a creature with power 4 or greater.
Bonk deals 4 damage to any target.

Whenever a nontoken creature you control dies, you may pay that creature's mana cost. If you do, search your library for a card and put it into your hand, then shuffle.

Exile target creature or planeswalker, then exile its controller's graveyard.

Each opponent discards all the cards in their hand, then draws that many cards. You discard your hand, then draw cards equal to the number of cards your opponents drew this turn.

Exile up to two target artifacts, creatures, and/or enchantments you control. Return those cards to the battlefield under your control at the beginning of the next end step.

At the beginning of your end step, any number of target players mill three cards.
{5}{U/B}, {T}: You may cast target instant or sorcery card from an opponent's graveyard without paying its mana cost. Activate only as a sorcery.

Vigilance
Each nontoken creature you control gets +1/+1 for each other creature on the battlefield with the same name as it.

Flying
Whenever a creature enters under an opponent's control, you may pay {1}{B}. If you do, fateseal 1. (Look at the top one cards of an opponent's library, then put any number on the bottom and the rest on top in any order.)

Enchant creature
Whenever enchanted creature becomes tapped, return it and Driven to Distraction to their owner's hands.

When Grisly Reaper enters, you may exile a creature card from your graveyard. When you do, create a 1/1 black Skeleton creature token.

Sacrifice another creature: Put a +1/+1 counter on Skieryg Menace.

Trample
Chosen one ({W}{U}{B}{R}{G}: Transform this permanent.)

Disgraced 1 (This enters with a -1/-1 counter. Whenever it deals combat damage to a player, remove all -1/-1 counters from it.)
At the beginning of each player's upkeep, put a -1/-1 counter on target creature that player controls.

{B}, Discard a card: Post a bounty on target creature. (Put a bounty counter on that creature. It has “When this creature dies, each opponent draws a card” as long as it has a bounty counter on it.)

Equipped creature gets +1/+0 for each artifact you control.
Equip—Sacrifice an artifact.

Flying
When Krothuss, Abyssal Terror dies, return all creatures to their owners' hands except for Krakens, Leviathans, Octopuses, and Serpents.
Foreshadow {6}{U}{U} (You may cast this spell for its foreshadow cost. If you do, also trigger its “dies” abilities when it enters.)

{1}{U}: Exile Elusive Monkey. Return it to the battlefield under its owner's control at the beginning of the next end step.