msem-instigator

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.

{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.)

Deathtouch
At the beginning of each opponent's upkeep, that player loses 1 life.

{T}, Sacrifice an artifact or creature: Each opponent loses 1 life and you gain 1 life.

When Duncaster Nightwatcher enters and whenever you cast a noncreature spell, create a 1/1 colorless Human creature token.
Whenever you attack with three or more creatures, return target noncreature, nonland card with mana value 3 or less from your graveyard to your hand.

Whenever you scry, put a +1/+1 counter on Dunesea Cartographer for each card you looked at while scrying this way.
{3}{W}{U}: Scry 2.

When Dusk Lieutenant enters, forebode. (Create a tapped colorless Omen artifact token with “{T}, Discard a card, Sacrifice this artifact: Draw a card.”)
Once each turn, when you discard a card during your turn, each opponent discards a card.

Vision (Whenever this or another creature you control enters, reveal the top card of your library. Then you may put that card into your graveyard.)
Whenever Dusk Occultist envisions a creature card, draw a card.

Improve {1}{B} ({1}{B}: Put a +1/+1 counter on this creature. This costs {1} more to activate for each +1/+1 counter on it. Improve only as a sorcery.)
Once each turn, when you gain life, you may have each opponent loses 1 life.

Poisonous 1 (Whenever this creature deals combat damage to a player, that player gets a poison counter.)
Duskscale Marauder can't be blocked.

Whenever Duskwatcher attacks, create a Function token with “Tap target creature.” (It's an enchantment. As you cast an instant or sorcery spell, sacrifice any number of Functions to add their effects to that spell.)

Each other nontoken Elf and/or Warrior you control enters with an additional +1/+1 counter on it.
{G}{G}, {T}, Remove two +1/+1 counters from among creatures you control: Create two 1/1 green Elf Warrior creature tokens.

Landfall — Whenever a land you control enters, Duskwood Vanguard gets +1/+1 until end of turn.

Landfall — Whenever a land you control enters, you may pay {1}{G}. If you do, create a 2/2 green Wolf creature token.

Dutiful Chasqui gets +2/+1 as long as you control two or more other creatures that share a name with it.
A deck can have any number of cards named Dutiful Chasqui.

When Dutiful Counselor enters, adjudicate. (Create a white Aura enchantment token with enchant creature and “Sacrifice this token: Untap enchanted creature” attached to target creature.)
Whenever an Aura you control enters, you may pay {1}. If you do, target creature gets +1/+1 until end of turn.

Reach

Prowess
Whenever you cast an instant or sorcery spell, if its mana value is less than or equal to Dwarven Twinslinger's power, copy that spell. You may choose new targets for the copy.

When Dylso Charmer enters, if you cast it from exile, create a 2/2 white Cat creature token.
Prophecy {1}{G} (Once each turn, you may exile a card with prophecy as you reveal it. When you do, you may cast it for its prophecy cost as long as it's exiled.)

Haste
Whenever Eager Guide attacks, tap up to two target creatures you don't control.

Eager Observer gets +1/+1 as long as you control an artifact or enchantment.

{4}{G}{G}: Eager Voyager voyages. (If it isn't blocking or targeted by another spell or ability, it phases out.)
Whenever Eager Voyager phases in, if it has no +1/+1 counters on it, put four +1/+1 counters on it.

Creatures you control enter with a +1/+1 counter on them if you spend three or more colors of mana to cast them.

{1}{R}: Earnest Labourer gets +2/+0 until end of turn.
{4}{G}: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.