msem-instigator

Whenever Precursor Omniprocessor attacks, you may sacrifice an artifact or creature. If you do, put a +1/+1 counter on Precursor Omniprocessor and it gains menace until end of turn.
Crew 2 (Tap any number of creatures you control with total power 2 or greater: This Vehicle becomes an artifact creature until end of turn.)

Equipped creature gets +1/+1 and has menace.
Equip {R}

Predatory Abomination has deathtouch and lifelink as long as you control another Horror.

Choose a creature. When it dies this turn, distribute two +1/+1 counters among any number of creatures you control.

If one or more +1/+1 counters or quest counters would be put on a permanent you control, that many plus one of those counters are put on it instead.

Target creature you control gains double strike until end of turn. That creature also gains trample until end of turn if you control a creature with power 4 or greater.

Enchant creature
Enchanted creature gets +0/+1 and has hexproof.
Mirage {U} (You may cast this spell as though it had flash for its mirage cost. If you do, sacrifice it at the beginning of the next cleanup step.)

Search your library for a creature card, reveal it, put it into your hand, then shuffle. Then if you control a creature with power 4 or greater, you may pay {4}. If you do, you may put a creature card from your hand onto the battlefield.

Counter target spell unless its controller pays {1} for each card in their graveyard.

Draw two cards, then discard two cards. Then if you cast Price of Wisdom from your graveyard, create a 3/3 blue Sphinx creature token with flying.
Flashback {4}{U}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Prowess, haste
Whenever you cast an instant or sorcery spell, you may shuffle the cards in your hand into your library, then draw that many cards.

Each player can't untap more than one nonbasic land during their untap step.

{T}: Add {C}.
Whenever you tap Primal Channeler for mana, the next creature spell you cast this turn can be cast as though it had flash.

Trample
Primitive Berserker's power is equal to the number of Goblins you control.

{2}: Add one mana of any color.

Enchant land
Whenever enchanted land is tapped for mana, its controller adds an additional one mana of any color that land could produce.

Lifelink
Heretic (Whenever you cast a spell that doesn't share a color with this creature, it gets +1/+1 until end of turn.)

Once each turn, when one or more artifacts you control deals damage to an opponent, you may exile the top card of your library. You may play that card this turn. The same is true for enchantments, planeswalkers, instant spells, and sorcery spells.

When you cast this spell, you may sacrifice a creature. If you do, copy this spell. (Copies keep functions.)
Search your library for a land card, reveal it, put it into your hand, then shuffle.

Exile target creature, enchantment, or planeswalker. You lose life equal to its mana value.

Discard a card, then return up to two creature cards from your graveyard to your hand.

Profane Emissary gets +2/+2 and has lifelink as long as you control a Demon.
If you would draw a card, you may instead search your library for a Demon card, reveal it, put it into your hand, then shuffle. You lose life equal to that card's mana value.

Kicker {2} (You may pay an additional {2} as you cast this spell.)
Counter target spell if its mana value is 2 or less. If this spell was kicked, counter that spell if its mana value is 4 or less instead.

When Project Head enters, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)
{2}{U}, Exile Project Head: Shuffle your hand and graveyard into your library, then draw seven cards. Activate only if you control seven or more artifacts.

As long as another creature you control is attacking, Prolific Thief can't be blocked.
Whenever Prolific Thief deals combat damage to a player, draw a card, then discard a card.