msem-instigator

First strike
Revive {4}{W} ({4}{W}, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

At the beginning of your upkeep, create two 1/1 colorless Construct artifact creature tokens, then you gain life equal to the number of artifacts and enchantments you control.

When Patrol Droid dies, if it attacked this turn, conjure a card named Data-Point into your hand. (It's a sorcery that costs {2} with “Draw a card.”)

Equipped creature gets +2/+1.
Equip multicolored creature {1}
Equip {2}

Gleaming Veldt enters tapped unless another player controls a land that could produce {G} or {W}.
{T}: Add {G} or {W}.

When Pantheon Breaker enters, each opponent sacrifices an enchantment.

Advance {2}{W} (Cast this for {2}{W} to advance it as it enters. {2}{W}: Advance this as a sorcery.)
Whenever Construct Engine advances, create a 1/1 colorless Construct artifact creature token.

({T}: Add {B}.)
As Stygian Dunes enters, you may pay 1 life. If you don't, Stygian Dunes enters tapped.

Primal {1}{W}{W} (During your turn, you may cast this spell for {1}{W}{W} instead of playing a land.)
Double strike
When Sunken Slasher enters, if you didn't play a land this turn, put a +1/+1 counter on it.

If a creature entering under you control causes an ability to trigger, you may pay -1. Whenever you do, copy that ability. You may choose new targets for the copy.
[+1]: Exile target creature. Return that card to the battlefield tapped under its owner's control at the beginning of the next end step. If you don't control it, it enters with a stun counter.
[–2]: Draw a card and gain 2 life.

When Woopip Elder enters, germinate. (Put a +1/+1 counter on a creature or create a 1/1 green Saproling creature token.)

Choose target permanent. Take an extra turn after this one. During that turn's untap step, permanents other than the chosen permanent phase out until end of turn. Exile Time Stands Still.

Exile target nonblack creature. Its controller exiles a card at random from their hand.

Equipped creature gets +1/+1.
Equip {1}

When Postmortem Contemplation enters, draw a card.
{1}{U}: Draw a card, then discard a card.

Whenever a nontoken creature you control enters, create a 1/1 colorless Human creature token.

Spirited (When this creature enters, you may activate one of its activated abilities without paying its cost.)
{3}{R}{W}: Creatures you control gain flying and haste until end of turn.

Enchant creature
When Hypnotic Halo enters, create an Idol token. (It's an artifact with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)
{2}{W}{W}, Sacrifice Hypnotic Halo: Exile enchanted creature.

[+1]: Until end of turn, whenever target creature deals combat damage to a player, that player mills two cards.
[–1]: Tap target creature. It can't become untapped for as long as you control Vaertris, Mindmelder.
[–6]: You get an emblem with “Whenever you draw a card, target player mills three cards” and “{2}{U}: Draw a card.”

Chronicle (As this enters and after your draw step, add a lore counter. Stop after III.)
[Lore I-II] Put a +1/+1 counter on up to one other target creature you control.
[Lore III] Target creature must be blocked this turn if able.

Destroy target nonbasic land.

Discard your hand, shuffle your library, then draw three cards. You may cast a nonland card from your hand without paying its mana cost.
Acquiesce (If you cast this spell from your hand, exile it as it resolves. When one or more creatures you control deal combat damage to an opponent, you may cast this card from exile without paying its mana cost.)

Haste
Fleeting {B} (You may cast this spell for its fleeting cost. If you do, sacrifice it at the beginning of the next end step.)

As an additional cost to cast this spell, sacrifice a creature.
Faith Burns Brightest deals damage equal to the sacrificed creature's power to any target.
Acquiesce (If you cast this spell from your hand, exile it as it resolves. When one or more creatures you control deal combat damage to an opponent, you may cast this card from exile without paying its mana cost.)

Flash
Oscanthor, Trader's Ruin can't be blocked.
Whenever a creature you control deals combat damage to a player, draw a card.