msem-instigator

When Dragon-Forged Armor enters, exile a creature card from a graveyard.
Equipped creature gets +X/+Y, where X is the power of the last creature card exiled with Dragon-Forged Armor and Y is its toughness.
Equip {2}

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

{2}: Dragonfire Longboat gets +1/+0 until end of turn.
Crew 1 (Tap any number of creatures you control with total power 1 or greater: This Ship Vehicle becomes an artifact creature until end of turn.)

{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.

Defender
A deck can have any number of cards named Dragonwall Fragment.
At the beginning of your upkeep, if you control twenty or more creatures named Dragonwall Fragment, you win the game.

{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.)

Flying
When Dreadstone Watcher dies, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Menace
Crew 3 (Tap any number of creatures you control with total power 3 or greater: This Vehicle becomes an artifact creature until end of turn.)

Puzzlebox (Begin the game with this and another card you own from outside the game in the command zone, locked. That card is face down until you unlock this.)
{0}: If a player has fifteen or fewer cards in their library, unlock Dreamcast Relic. If the revealed card is blue, put it into your hand. Otherwise, put it on top of your library.

Dreamscape enters tapped with two charge counters on it.
{T}: Add {C}.
{T}, Remove a charge counter from Dreamscape: Add one mana of any color.

({T}: Add {W} or {B}.)
Dreary Township enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

When Drift Tracer enters, search your library for a basic land card that shares a type with a basic land you control and put it onto the battlefield tapped, then shuffle.

As Drop of Envy enters, choose a nonland permanent card name.
All cards not on the battlefield, spells, and permanents with the chosen name are legendary.

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

Enchant creature
Enchanted creature doesn't untap during its controller's untap step.

Equipped creature is a Dragon and has base power and toughness 4/4, flying, and “{2}: This creature gets +1/+0 until end of turn.”
Equip {3}

{2}: Duela Duelist gains first strike until end of turn.
{3}: Duela Duelist gains distorted until end of turn. (This creature can be blocked by tapped creatures but not untapped creatures.)

Whenever you cast an instant or sorcery spell, you may untap Duela Science Kit.
{T}, Tap an untapped creature you control: Catalyze. (The next spell you cast this turn costs {1} less to cast.)

Equipped creature gets +1/+1.
Equipped creature can't be blocked by more than one creature.
Equip {1}

Dunesea Expanse enters tapped unless you control another Desert.
{T}: Add {W} or {U}.

({T}: Add {B} or {G}.)
Duskwood Thicket enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

{T}: Add {C}.
{T}: Target player exiles a nonland card from their graveyard.

Dustchoked Outpost enters tapped.
When Dustchoked Outpost enters, create a 1/1 Scout creature token that's all colors. It gains haste until end of turn. Sacrifice it at the beginning of the next end step.
{T}: Add {R}.