msem-instigator

Instant and sorcery spells you cast cost {1} less to cast.

When Disciple of the Buried Glade leaves the battlefield, create a 3/3 green Elemental creature token.

When Diseased Prophet enters, each opponent loses 1 life.
Revive {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.)

Whenever you or a creature you control become the target of a spell or ability an opponent controls, that opponent gets a spite counter.

Whenever a creature is returned to its owner's hand, draw a card.
{4}{U}{U}: Return target creature to its owner's hand.

{T}: Target creature gets -2/-0 until end of turn.

Whenever Distracting Performer becomes tapped, you may tap target creature.

{1}, {T}, Move a -1/-1 counter from another creature onto Dockside Healer: You gain 2 life.

Whenever Dodgy Infant becomes the target of a spell, you may change the target to another creature you control.

Spirited (When this creature enters, you may activate one of its activated abilities without paying its cost.)
{5}{U/B}{U/B}: Gain control of target creature with mana value 3 or less until Dollmaster leaves the battlefield.

When Doom Cultist dies, target player loses 2 life and you gain 2 life.

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.

Deathtouch
When Doomed Explorer dies, create a Treasure token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color.”)

When Doomed Traveler dies, create a 1/1 white Spirit creature token with flying.

When Doomed Widow dies, create a 1/1 white Spirit creature token with flying.

When Doomed Woodsman dies, create a 1/1 green Faerie Druid creature token with hexproof.

{T}, Sacrifice an Equipment: Return target Equipment card from your graveyard to the battlefield. Activate only as a sorcery.

First mate — Twelve or more cards in your starting deck have “gain control” or “exchange control” in their printed rules text. (If this card outside the game is your chosen first mate, you may swap it with a card in your opening hand.)
Dr. Telsi of the Ark can't be blocked.
Dr. Telsi gets +1/+1 for each permanent you control but don't own.

{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.)

Haste
Dominance — {T}: Create a 5/5 red Dragon creature token with flying. Activate only if you control the creature with the greatest power or tied for the greatest power.

Instant, sorcery, and Dragon cadence (Whenever you cast an instant, sorcery or Dragon spell, if its mana value is greater than this creature's power, put a +1/+1 counter on this creature.)
{R}, {T}, Discard a card: Draw a card.

When this creature enters, you may sacrifice a creature. If you do, you draw a card and you lose 1 life.
Arise {2}{B} ({2}{B}, 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 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.

Dreamscaper enters tapped with three stun counters on it. (If it would become untapped, remove a stun counter from it instead.)
Whenever you cast your second spell each turn, you may untap Dreamscaper or tap target creature.
Whenever Dreamscaper deals combat damage to a player, draw two cards.

When Dregscape Wretch dies, create a 2/2 black Zombie creature token.