msem-instigator

When Dunecrest Pariah enters, you may search your library for a basic land or Desert card, reveal it, put it into your hand, then shuffle.
{T}, Sacrifice Dunecrest Pariah: You may put a land card from your hand onto the battlefield tapped.

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

Vigilance, ward {2}
{1}{G}, {T}: Put a +1/+1 counter on Dunetreader Tortoise. Activate only as a sorcery.

Target opponent reveals their hand. You choose a noncreature, nonland card from it. That player discards that card.

Whenever Dusk Insurgent perseveres, create a 1/1 white Warrior creature token. (A creature perseveres when it survives damage.)

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.

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.)

Landfall — Whenever a land you control enters, target creature you control gains vigilance until end of turn.

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

When Dutiful Camel enters, put a +1/+1 counter on target creature you control.

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

Whenever you cast an instant or sorcery spell, you may pay {1}. If you do, Dwarven Fireslinger deals 1 damage to each player.

When Dwarven Tunnelers enters, create a tapped Treasure token.
{T}: Target creature with power 2 or less can't be blocked this turn.

Investigate, then target creature gets -1/-1 until end of turn for each Clue you control. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

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.)

Whenever you cast a noncreature spell, Dynamic Wyvern gains flying until end of turn.

When Dynasty Infantry enters, choose one —
• Search your library for a card named Dynasty Infantry, reveal it, put it into your hand, then shuffle.
• Put a +1/+1 counter on target creature you control.

Experience (Whenever this creature attacks, if it has fewer than three +1/+1 counters on it, put a +1/+1 counter on it.)
When Eager Hatchling has three or more +1/+1 counters on it, remove them all and transform it.

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

First strike (This creature deals combat damage before creatures without first strike.)

{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.