msem-instigator

Spells your opponents cast cost {1} more to cast.
Spells you cast cost {1} less to cast.

At the beginning of your end step, if you have no cards in hand, draw a card.
{2}{U}, {T}: Sacrifice any number of nontoken creatures. Create an X/X blue Horror creature token for each of those creatures, where X is the total power of those creatures.

{2}, Sacrifice Doctored Trail: Draw a card.
{T}, Sacrifice Doctored Trail: Destroy target Clue. If you do, draw a card.

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

Dominik's Shack enters tapped.
When Dominik's Shack enters, you may mill two cards.
{T}: Add {B} or {G}.

Equipped creature has first strike.
Whenever another creature you control dies, put a +1/+1 counter on equipped creature.
Equip {2}

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

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.

{T}: Add {G}.
{B/G}, {T}: Exile target card from a graveyard. If that card is a creature card, put a +1/+1 counter on Dovon, Verdant Experimenter and you gain 1 life.

Enchant opponent
When Down with the Ship enters, enchanted player discards a card unless they sacrifice a creature.
{1}{B}, Sacrifice Down with the Ship: Return target creature card from your graveyard to your hand.

Pressure {3}{U} (You may cast this spell for its pressure cost if seven or more cards are in your graveyard.)
Return target creature to its owner's hand. If this spell was cast for its pressure cost, put that creature into its owner's library second from the top instead.

Dragon Queen's Den enters tapped.
{T}: Add {U}.
{U}, {T}: Scry 1. Activate only as a sorcery and only if you control a blue creature.

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.

Dragon's Ire deals 1 damage to any target.
Inscribed creature gets +2/+2.
Inscribe {2}{R} ({2}{R}: Exile this card from your hand inscribed on a creature you control. Whenever that creature attacks, its controller may cast a copy of the inscribed card without paying its mana cost. Inscribe only as a sorcery.)

Equipped creature gets +2/+0.
Equipped creature has first strike as long as it's attacking.
Equip {3}

{T}: Add {C}.
{T}: Target land you control becomes the basic land type of your choice until end of turn.

Harmony — Add one mana of any color.
{1}, {T}: Harmonize. Then sacrifice Dragonglass Harp. (To harmonize, trigger up to one harmony of a permanent you control.)
When Dragonglass Harp is put into a graveyard from the battlefield, draw a card.

{T}: Add {C}.
Tap an untapped creature you control: Dragonwall Gates becomes a 0/4 Wall artifact creature with defender until end of turn. It's still a land.

{T}: Add {C}.
{T}, Reappropriate: Add {G} or {U}. (Exile exactly two cards from your hand and/or graveyard.)

Drakon Nightshade can't block.
When Drakon Nightshade dies, scry 1.

Dramatic Peril deals damage equal to the number of lands you control to any target. (Cast a copy of this spell once while this creatures is on the battlefield.)