msem-instigator

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.

Flash
Wanderlust — When Microzoologist enters, search your library for a creature card with mana value 1. If you control four or more differently named lands, you may search for a creature card with mana value 3 or less instead. Reveal that card, put it into your hand, then shuffle.

Vigilance
When Mid-Autumn Celebrants enters, create a 2/2 white Panda Bear Monk creature token with vigilance.

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.

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.

({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}.”

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

Flash

Whenever you cast a spell from exile, put two +1/+1 counters on Midnight Vagrant. It gains menace until end of turn.
{1}{B}{B}: Exile the top card of target opponent's library. You may play that card during any turn you attacked with a Rogue, and you may spend mana as though it were mana of any color to cast it. Activate only as a sorcery.

Flying
When Midnight Visitor enters, you may return target creature to its owner's hand.

{T}, Mill a card: Add {G}.
{X}{U}{B}, {T}, Exile a permanent card with mana value X from your graveyard: Create a tapped token that's a copy of it, except it's an X/X Elemental creature in addition to its other types.

When Miede-District Alchemist enters, add {R}{R}{R}.
Paranoia {1}{R} (You may cast this spell for its paranoia cost when a permanent you control leaves the battlefield.)

Haste
{R}, {T}: Miede-District Enforcer deals 2 damage to target creature that entered this turn or player that cast a creature spell this turn.
Paranoia {1}{R} (You may cast this spell for its paranoia cost when a permanent you control leaves the battlefield.)

Golden age (If you cast an instant or sorcery spell, activated a nonmana ability, and attacked this turn, enter a renaissance for this game.)
{1}{R}: Mieng gains flying until end of turn.
Whenever Mieng attacks, create a 4/4 red Dragon creature token with flying that's tapped and attacking. Exile that token at end of combat unless you're in a renaissance.

Ferocious — Whenever a creature with power 4 or greater you control enters, Mieng, Who Dances With Dragons becomes a 4/4 Dragon creature with flying until end of turn.

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

Flash
When Mighty Beetle enters, you may put two +1/+1 counters on target creature you control.

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

Golden age (If you cast an instant or sorcery spell, activated a nonmana ability, and attacked this turn, enter a renaissance for this game.)
Mighty Xioshu can't be blocked by creatures with power 2 or less as long as you're in a renaissance.

You may exert Migrating Herd as it attacks. When you do, sacrifice a land and draw a card. (An exerted creature won't untap during your next untap step.)

(Add a quest counter as this enters. Sacrifice after 3.)
Whenever you cast a legendary spell, add a quest counter.
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.
You gain 5 life.
Destroy all nonlegendary creatures.

Vigilance
Whenever Mikkino becomes blocked by a creature with power 3 or greater, exile that creature.

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.)