msem-instigator

Pressure {3}{U}{B} (You may cast this spell for its pressure cost if seven or more cards are in your graveyard.)
Destroy up to one target creature. Return all other nonland permanents to their owners' hands.

Flying, first strike, haste
Whenever Doombringer Dragon attacks, you may sacrifice another creature. If you do, Doombringer Dragon gets +3/+0 until end of turn.

Haste
When Doomed Alchemist dies, create two Treasure tokens. (They're artifacts with “{T}, Sacrifice this artifact: Add one mana of any color.”)

Double strike, trample
Enchantment spells you cast cost {1} less to cast.
Whenever you put a lore counter on a Saga you control, Douglass, Star of the Show gets +1/+1 until end of turn.

{2}{U}{B}, Sacrifice a creature: Return target creature card from your graveyard to the battlefield with a finality counter on it. It gains myriad. (Whenever it attacks, for each opponent other than defending player, you may put a token that's a copy of this creature onto the battlefield tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)

Harmony — Draw a card, then discard a card.
Whenever Dramatic Artist attacks, harmonize. (Trigger up to one harmony of one permanent you control.)

Flying, menace
When Dreadfire Tyrant enters, target opponent reveals their hand. You may put a creature or planeswalker card from it onto the battlefield under your control. That permanent gains haste and “At the beginning of your end step, sacrifice a permanent you control.”
When Dreadfire Tyrant dies, each opponent loses 5 life. You gain life equal to the life lost this way.

At the beginning of your end step, mill two cards and you lose 2 life.
Arise {3}{B}{R} ({3}{B}{R}, Exile this from your graveyard as a sorcery: Create a black token copy of it that's also a Zombie and can't block.)

When this enchantment enters, create a 1/1 white Peasant creature token.
{B/R}, Sacrifice a creature: Exile the top card of your library. You may play that card this turn.

When Dream Keeper enters, each player conjures a card named Fatigue and puts it on top of their library. (It's a colorless sorcery that costs {2} with “Draw a card.”)
Whenever a player draws a card except the first one they draw in each of their draw steps, each opponent mills a card.

Scry 1, then draw two cards. You gain 3 life. Exile up to four cards from graveyards.

When Dreamsight Well enters, shuffle any number of cards you own from outside the game into your library.
Whenever you cast a creature spell, if you have more cards in your library than each opponent, draw a card.

You may look at the top card of your library any time.
You may play the top card of your library if it's a land card or a creature card with power 2 or less.

Each player mills five cards.
Coalesce {4}{U}{B} (You may cast this from your graveyard for {4}{U}{B}. If you do, it enters as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)
Drink Thoughts Like Oil can't be blocked.

When Drop Bear enters, return another target permanent that isn't a land an opponent controls or a card in a graveyard to its owner's hand.

Flying
Whenever you cast a spell during an opponent's turn, Drosera and Nerium deals 1 damage to each opponent.
As long as Drosera and Nerium is tapped, you may cast spells as though they had flash.

Flying
Whenever a creature you control dies, put a +1/+1 counter on Drove of the Lost.
{1}, Sacrifice a creature: Each opponent loses 1 life. Gain 1 life.

Menace
Spells you cast from your graveyard cost {2} less to cast.
Whenever Drownyard Captain attacks, if a card left your graveyard this turn, draw a card.

Whenever Drownyard Colossus or another creature you control enters, any number of target players each mill cards equal to that creature's toughness.
{2}{U}{B}, {T}: Draw a card, then create a 0/3 blue Crab creature token with “{T}: Target player mills a card.”

Menace, haste
Whenever another creature dies, you get a blood counter.
{B}{R}, Pay two blood counters: Return Dthan, Who Bloodies the Sands from your graveyard to the battlefield.

Double strike
{3}{R}{W}: Create Hao'Tai's Blessing, a legendary red and white Aura enchantment token with enchant creature and “Enchanted creature gets +3/+3 and has flying” and attach it to Duan, the Fabled Rider.

When Duchess Odelia VII enters, search your library for a nonland permanent card with mana value 1 or less, reveal it, put it into your hand, then shuffle.

If an opponent controls more lands than you, search your library for up to three basic land cards, reveal them, put them into your hand, then shuffle.

First strike, menace
Whenever Dueling Duo or another creature you control becomes blocked, that creature deals 1 damage to each creature blocking it.

Target creature gets +2/+0 until end of turn and can't be blocked except by three or more creatures this turn.
Flashback {U/R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)