msem-instigator

If you would look at or reveal one or more cards of a library, you may first search that library for that many cards, shuffle that library, then put those cards on top of it in any order.

Menace
Whenever a creature dies, you gain life equal to its power.
Reappropriate: Put a +1/+1 counter on The Cannibals of Kallio Hill, then lose life equal to its power. (To reappropriate, exile exactly two cards from your hand and/or graveyard.)

Enchant creature
Enchanted creature has base power and toughness 1/1, and its activated abilities can't be activated.

When The Clocktower Project enters, create a tapped colorless Powercell artifact token with “{T}: Add {C}.”
Tap seven untapped artifacts you control: Draw three cards.

Instant and sorcery spells you control have rerun. (Exile the spell as it resolves if you cast it from your hand. Whenever a creature you control dies, you may cast that card from exile without paying its mana cost.)

{T}, Pay 1 life: Add {R}.
{6}{R}{R}, Exile The Court of Angels from your hand: Destroy all artifacts, creatures, and lands. They can't be regenerated.

Other permanents you control have hexproof.
Prevent all damage that would be dealt to other permanents you control.

First strike
At the beginning of your end step, each opponent that lost life this turn loses 1 life and discards a card. You gain life equal to the life lost this way, then draw a card for each land card discarded this way.

{T}, Sacrifice X lands: Search your library for a nonland card with mana value X, cast it without paying its mana cost, then shuffle.

Target player discards two cards.
Ferocious — That player discards two cards at random instead if you control a creature with power 4 or greater.

Whenever The Dreamer enters or you play a card exiled with them, exile the top two cards of your library face down, then another face up.
You may play face up cards exiled with The Dreamer.
{T}, Sacrifice The Dreamer: Look at each face down card exiled with The Dreamer. You may cast one without paying its mana cost.

Flying, menace
Whenever another creature you control deals combat damage to a player, sacrifice it.
If you would draw a card, you may instead return a creature card from your graveyard to your hand.

Menace
When The Duneborn Host enters, mill four cards.
Whenever a card is put into your graveyard from anywhere, each opponent loses 1 life and you gain 1 life.
Whenever a card leaves your graveyard, create a 2/2 black Zombie creature token.

At the beginning of your upkeep, destroy target creature with the greatest power or tied for greatest power among creatures on the battlefield. Then if there are no creatures on the battlefield, sacrifice The Empty Throne.

Death knell — All creatures get -1/-1 until end of turn. (As a creature you control dies, trigger one death knell of that creature or another permanent you control.)
{B}, Sacrifice a creature: Choose a card in your graveyard with mana value less than the sacrificed creature's mana value. You may cast it without paying its mana cost.

Cards in graveyards, exile, and libraries lose all abilities and card types.

Whenever The Ever-Pestilent deals combat damage to a player, that player discards a card at random.

Whenever a creature an opponent controls dies, its controller loses 1 life.
At the beginning of each opponent's upkeep, put a -1/-1 counter on each creature that player controls.

Whenever The Feller of Greatwoods enters or attacks, you may sacrifice two noncreature permanents. For each permanent sacrificed this way, reveal the top five cards of your library. You may put a creature card from among them onto the battlefield and the rest into your graveyard.

Whenever The First Idol attacks, create an Idol token. (It's an artifact with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)
Sacrifice three Idols: Return The First Idol from your graveyard your hand.

Whenever an opponent activates an ability of a nonland permanent, destroy that permanent.
{3}{U}{B}{R}: Exile target creature or planeswalker card in a graveyard. Create a token that's a copy of it.

Destroy target tapped creature.
Reconstruct {4}{W} (You may cast this from your graveyard for its reconstruct cost reduced by the mana value of a permanent you sacrifice as you cast it this way. Then exile this.)

[+1]: Return target nonland permanent to its owner's hand. That player loses 2 life.
[0]: Create a 1/1 blue Bird creature token with flying for each loyalty counter on The Flock.
[–6]: You get an emblem with “If a permanent you don't control would leave the battlefield, you may instead exile it, then return that card to the battlefield under your control. It's a 1/1 blue Bird creature with flying.”

Destroy all nonland permanents. Draw a card for each card type among cards in graveyards.

[+1]: Create a 0/1 blue Illusion creature token.
[–2]: Put target creature on top of its owner's library.
[–6]: You get an emblem with “Whenever you draw a card, target opponent mills six cards.”