msem-instigator

Enchant land
Enchanted land has “{T}: Put a +1/+1 counter on target creature you control. Activate only as a sorcery.”

(Add a quest counter as this enters. Sacrifice after 3.)
Once each turn, when a player discards a card, you may add a quest counter.
1, 2 — Each opponent loses X life and you gain X life, where X is the number of quest counters on Gloomhollow Expedition.
3 — Choose up to two target creature cards in graveyards with total mana value 3 or less. Put those cards onto the battlefield under your control.

Thawing Valley enters tapped unless you control a basic land.
{T}: Add {G} or {U}.

This spell costs {1} less to cast for each instant and sorcery card in your graveyard.
Fiery Explosion deals 5 damage to target creature or planeswalker.

Forgotten Consequences deals 2 damage to target attacking or blocking creature.

At the beginning of the next end step, create X 1/1 white Spirit creature tokens with flying, where X is the number of creatures that died this turn.
Reconstruct {2}{W}{B} (You may cast this from your graveyard for its reconstruct cost reduced by the mana value of a permanent you sacrifice as you cast it this way. Then exile this.)

Haste
The first instant or sorcery spell you cast each turn costs {1} less to cast.
{R}, {T}, Sacrifice Hellspark Prankster: Change the target of target spell with a single target.

Whenever you draw a card, put a foreshadow counter on Ominous Seas.
Remove eight foreshadow counters from Ominous Seas: Create an 8/8 blue Kraken creature token.
Cycling {2} ({2}, Discard this card: Draw a card.)

Deathtouch
When Doomed Explorer dies, create a Treasure token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color.”)

Enchant creature you control
Enchanted creature gets +1/+1.
{1}{U}: Return Lightning Draw and enchanted creature to their owners' hands.

Whenever you cast an instant, sorcery, or Wizard spell, Slipsand Runemage deals 1 damage to any target.

Whenever Arisen Helix attacks, scry 2.
If Arisen Helix would die, exile it instead.

Cliffside Entrance enters tapped unless you have 15 or less life.
{T}: Add {R} or {W}.

Whenever Withering Husk enters or attacks, you may discard a card and pay 1 life. If you do, draw a card, then each opponent loses 1 life.
Recite {R} (You may cast this creature from your graveyard for its recite cost. If you do, exile it when it enters or if it would leave the battlefield.)

Until end of turn, target creature you control gains hexproof and has base power and toughness 4/4. (It can't be the target of spells or abilities your opponents control.)
Draw a card.

{T}: Add {C}. Put a fusion counter on Eternal Reactor.
{2}, {T}: Add {C} for each fusion counter on Eternal Reactor.

Haste
Dominance — {T}: Create a 5/5 red Dragon creature token with flying. Activate only if you control the creature with the greatest power or tied for the greatest power.

Prowess, trample
During your turn, each instant and sorcery card in your graveyard has flashback. The flashback cost is equal to that card's mana cost plus “Pay X life, where X is this card's mana value.”

Target creature you control gets +3/+0 until end of turn. Other creatures you control get +1/+0 until end of turn.

Flash (You may cast this spell any time you could cast an instant.)
When Stasis Snare enters, exile target creature an opponent controls until Stasis Snare leaves the battlefield.

Return target permanent to its owner's hand. Then that player discards a card.

When Hashiro's Vanguard enters, each player sacrifices a nontoken creature.

[+1]: Move a counter from up to one target permanent onto another permanent that shares a type with it.
[–1]: Target creature gets -1/-3 until end of turn.
[–5]: Search target opponent's library for a creature or planeswalker card and put that card onto the battlefield under your control. Then that player shuffles.

Put target creature into its owner's library third from the top.