msem-instigator

{T}: Add {C}.
{3}{G}: Until end of turn, Damian's Undercity becomes a 2/2 creature. It's still a land. It has lifelink if {W} was spent to activate this ability, gets +0/+3 if {U} was spent, and has deathtouch if {B} was spent.

{T}: Add {C}.
Satrapies you control have “{1}{G}, {T}: Put a +1/+1 counter on target creature. Activate only as a sorcery.”

As Danaj Fortress enters, you may pay 1 life. If you don't, Danaj Fortress enters tapped.
Satrapies you control have “{T}: Add {G}.”

Danaj Sanctuary enters tapped.
Satrapies you control have “{T}: Add {G} or {U}.”

Danaj Temple enters tapped.
Satrapies you control have “{T}: Add {B} or {G}.”

Equipped creature gets +2/+2.
Equip {3}

Whenever equipped creature attacks, create a token that's a copy of it and that's tapped and attacking, except that token isn't legendary if equipped creature is legendary. Exile that token at end of combat.
Equip {3}

({T}: Add {R} or {G}.)
As Dangerous Territory enters, you may pay {1}. If you don't, Dangerous Territory enters tapped.

You may have Darksteel Mirror enter as a copy of any permanent on the battlefield, except it has indestructible in addition to its other abilities.

When Darna's Grimoire enters, you may discard a card. If you do, draw a card.
{2}, Sacrifice Darna's Grimoire: Draw a card.

Draw a card.

When Datalith enters, conjure a card named Data-Point into your hand. (It's a sorcery that costs {2} with “Draw a card.”)
{T}: Add one mana of any color.

{T}, Sacrifice Daunting Skyline: Search your library for a Plains or Swamp card and put it onto the battlefield tapped, then shuffle.

Dawn Hill Outskirts enters tapped unless you played it from exile.
{T}: Add {R} or {W}.

At the beginning of combat on your turn, choose one —
• Equipped creature gets +2/+0 and gains first strike until end of turn.
• Equipped creature gets +0/+2 and gains vigilance until end of turn.
Equip {3}

Dawnlit Battlefield enters tapped.
{T}: Add {R} or {W}.
{2}{R}{W}: Until end of turn, Dawnlit Battlefield becomes a 4/2 red and white Warrior creature with with “This creature has first strike as long as it's attacking” and “Whenever this creature attacks or blocks, torment yourself.” It's still a land. (To torment yourself, lose 3 life unless you discard a card or sacrifice a nonland permanent.)

When Dawson's Loot enters, mill two cards, then draw a card.
{1}, {T}, Sacrifice Dawson's Loot: Add one mana of any color.

Equipped creature gets +4/+2.
Equip—Sacrifice a creature. (Sacrifice a creature: Attach to target creature you control. Equip only as a sorcery.)

Dead Man's Hand enters tapped.
{T}, Sacrifice Dead Man's Hand, two permanents with mana value 1, and two permanents with mana value 8: Target player loses the game.

Deadwood Grove enters tapped.
{T}: Add {B} or {G}.
{1}{B}{G}: Until end of turn, Deadwood Grove becomes a 2/3 black and green Horror creature with with deathtouch and “Whenever this creature attacks or blocks, torment yourself.” It's still a land. (To torment yourself, lose 3 life unless you discard a card or sacrifice a nonland permanent.)

{4}, {T}, Exile Deathwind Detonator: Destroy all nonland permanents. Each player gets an emblem with “At the beginning of your upkeep, you lose 1 life.”

{T}: Add {C}.
{T}, Exile two cards from your graveyard: Add {W} or {B}.

{T}: Put a flood counter on Decanter of Endless Rivers. Add {U} for each flood counter on it.

Decayed Bedchamber enters tapped.
When Decayed Bedchamber enters, look at the top card of your library. You may put it into your graveyard.
{T}: Add {B} or {G}.

{T}, Sacrifice Decrepit Crags: Search your library for a Swamp or Mountain card and put it onto the battlefield tapped, then shuffle.