msem-instigator

Descended Hollow enters tapped.
{T}: Add {U} or {B}.
Morph {2} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Descended Marsh enters tapped.
{T}: Add {B} or {G}.
Morph {2} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Descended Meadow enters tapped.
{T}: Add {G} or {U}.
Morph {2} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Descended Mortuary enters tapped.
{T}: Add {W} or {B}.
Morph {2} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Descended Towers enters tapped.
{T}: Add {R} or {W}.
Morph {2} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Whenever an opponent fails a trial, create a 1/1 white Angel creature token with flying.

Destroy each artifact with mana value X or less, then create an Idol token for each artifact destroyed this way. (It's an artifact with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)

Desert Slaughterer can't block.
{B}, Remove a +1/+1 counter from a creature you control: Return Desert Slaughterer from your graveyard to the battlefield with a +1/+1 counter on it.

Desert Temple enters tapped.
As Desert Temple enters, an opponent of your choice chooses Oasis or Desiccation.
• Oasis — {T}: Add one mana of any color.
• Desiccation — {T}: Add {C}{C}. You lose 1 life.

Create two 1/1 red and white Sand Warrior creature tokens.

Desert Wurms can't be blocked by creatures with flying.
When Desert Wurms enters, create two 6/6 red Wurm creature tokens with “This creature can't be blocked by creatures with flying.”
When Desert Wurms is put into a graveyard from anywhere, shuffle it into its owner's library.

({T}: Add {W} or {B}.)
Deserted Steppe enters tapped unless you control two or more basic lands.

As Deserted Trail enters, you may reveal a Swamp or Forest card from your hand. If you don't, Deserted Trail enters tapped.
{T}: Add {B} or {G}.

Gain control of target creature until end of turn. Untap that creature. It gains haste and menace until end of turn.

({T}: Add {W} or {B}.)
Desolate Barrens enters tapped.

Menace
Whenever Despair Scavenger attacks, you may have target creature get -1/-1 until end of turn.

Haste
Whenever Desperate Reconnoiterer becomes untapped, scry 1.

Target opponent reveals their hand. You choose a creature or planeswalker card from it. That player discards that card.

Target opponent loses 1 life for each creature they control. You gain 2 life for each Wizard you control.

As an additional cost to cast this spell, you may sacrifice a creature.
Return to the battlefield a creature card in your graveyard that was put there from the battlefield this turn.

Target creature you control gets +5/+5 until end of turn.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, destroy up to one target artifact.

Trial 3 (As you cast this spell, an opponent of your choice may pay 3 life. If they don't, they fail the trial.)
When Devilish Undoer enters, if the trial was failed, return target creature card from your graveyard to your hand.

Vigilance (Attacking doesn't cause this creature to tap.)

Defender
Whenever another player casts an instant or sorcery spell, Devouring Spellroot gets +2/+2 until end of turn.