msem-instigator

Create a 2/2 blue Jellyfish enchantment creature token with flying.
Flashback {4}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Whenever you discard a card, choose up to one that hasn't been chosen this turn —
• Draw a card.
• Tap target creature. Put a stun counter on it.
• Create a 2/2 blue Jellyfish enchantment creature token with flying.

Whenever a creature you control dies, each opponent loses 1 life and you gain 1 life.
{2}{B}: Create a 1/1 black Rat creature token with “This creature can't block.” Activate only if there are five or more creature cards in your graveyard.

Siphon (Each -1/-1 counter you put on your creatures up to their remaining toughness while casting this pays for {1}.)
You gain X life and draw X cards, where X is the number of creatures that died this turn.

Enchant opponent
Whenever Middleware or another Curse becomes attached to enchanted player, exile the top card of that player's library face down. For as long as that card remains exiled, you may look at it and you may play it. Mana of any type can be spent to cast that spell.

Once each turn, when you activate a nonmana ability, you may create a tapped 1/1 white Spirit creature token with flying.
{4}{W}{U}: You gain 1 life and draw a card.

Target opponent discards two cards, then sacrifices a creature.

({T}: Add {B}.)
As Midnight Gate enters, you may pay 1 life. If you don't, Midnight Gate enters tapped.
Basic lands you control have “{T}: Add {B}.”

Look at the top two cards of your library. You may shuffle.
Draw two cards. You lose 2 life.

Reveal the top three cards of your library and put them into your hand. If this spell was cast from your graveyard, each opponent loses life equal to the total mana value of those cards. Otherwise, you lose that much life.
Flashback {4}{B}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

{T}: Add {C}.
{3}: Mill two cards, then return Midnight Keep from your graveyard to the battlefield tapped.

Harvest (You may tap any number of creatures you control as you cast this spell. If you do, reduce this spell's mana cost by their total power.)
Destroy target creature.

Each player loses 2 life, discards two cards, sacrifices two creatures, then sacrifices two lands.

Creatures you control gain flying until end of turn if you control a creature with flying. The same is true for first strike, double strike, haste, hexproof, indestructible, lifelink, trample, vigilance, and prowess.

Choose one—
• Destroy target artifact.
• Target creature gets +4/+4 until end of turn.

Enchant creature
Enchanted creature gets +3/+3 and has trample.

Choose one —
• Destroy target artifact.
• You gain 4 life.

Reveal the bottom two cards of your library. You may put one of those cards into your hand. If you do, target creature gets +X/+X until end of turn, where X is that card's mana value.

Until end of turn, target creature gains double strike and damage dealt by it can't be prevented.
Fuse (You may cast one or both halves of this card from your hand.)

Target attacking creature gets +3/+0 until end of turn.

When Mighty Totem enters, scry 1.
{1}{G}, Sacrifice Mighty Totem: Target creature gets +3/+3 until end of turn.

Search your library for a basic Forest or Plains card, put that card onto the battlefield tapped, then shuffle.
{3}{W}, Exile Migration Range from your graveyard: Create two 1/1 green and white Elk Spirit creature tokens. Activate only as a sorcery.

(Add a quest counter as this enters. Sacrifice after 3.)
Whenever you cast a legendary spell, add a quest counter.
1 — Look at the top seven cards of your library. You may reveal up to two legendary cards from among them and put them into your hand. Put the rest on the bottom of your library in a random order.
2 — You gain 5 life.
3 — Destroy all nonlegendary creatures.

MiliCore Barracks enters tapped.
{T}: Add {B} or {R}.
{B}{R}, {T}: Create a Function token with “Deathtouch.” Activate only if an opponent lost life this turn. (It's an enchantment. As you cast an instant or sorcery spell, sacrifice any number of Functions to add their effects to that spell.)

When Militant Arms enters, create a 1/1 white Human creature token, then attach Militant Arms to it.
Equipped creature gets +2/+1.
Equip {3}