msem-instigator

Put target creature with power X or less on top of its owner's library.
Investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Target instant or sorcery card in your graveyard gains flashback until end of turn. The flashback cost is equal to its mana cost. (You may cast that card from your graveyard for its flashback cost. Then exile it. Mana cost includes color.)

At the beginning of your upkeep, mill a card.
Whenever you cast a spell from your graveyard, create a 2/2 green Wolf creature token.

{T}, Pay 2 life: Add {B}.
{T}: Add one mana of any color. Spend this mana only to cast spells from your graveyard or activate abilities of cards in your graveyard.

Until end of turn, target creature you control gains “{T}: This creature deals 1 damage to any target.”
Draw a card.

Enchant creature
When Grip of Paranoia enters the battlefield, enchanted creature's controller loses 2 life.
Enchanted creature gets -3/-1 and can't block.

Guardian of Dusk gets +X/+X, where X is the amount of life you've lost this turn.
When Guardian of Dusk has power 13 or greater, sacrifice it. If you do, you gain life equal to its power.

Untap up to two permanents you control during each other player's untap step.

First strike
Whenever Guardian of the Eclipse attacks, you may exile another target attacking creature you control, then return it to the battlefield under your control tapped and attacking.

Put up to X target noncreature, nonland permanents on top of their owners' libraries in any order.
You gain 6 life.

Guidestone enters the battlefield tapped.
{T}: Add {C}.
{2}, Sacrifice Guidestone: Draw a card.

Puzzlebox (Begin the game with this and another card you own from outside the game in the command zone, locked. That card is face down until you unlock this.)
{1}, Sacrifice two Clues: Unlock Hall of Lost Histories and put the revealed card into your hand.

As long as your deck contains only black and colorless cards, your minimum deck size is reduced by eight.

When Halskrow Street Scavenger enters the battlefield, if a creature died under your control this turn, create a 2/2 green Wolf creature token.

You don't lose unspent mana as steps and phases end except at end of turn.
Hand of the Chroma gets +1/+1 for each color of unspent mana you have.

If a player would gain life, that player adds that much {C} instead.

Lands you control are colorless lands named Wastes with “{T}: Add {C}” and lose all other card types and abilities.

Vigilance
Creature spells you cast cost {2} less to cast.
Other creatures you control can't attack or block.

Whenever a player casts a noncreature spell, create a 1/1 white Human Soldier creature token.
{1}{U}, Tap four untapped creatures you control: Counter target noncreature spell.

You may cast Hunter of the Moon-Serpent from your graveyard as long as you gained life this turn.

Exile target creature card from a graveyard. Create a token that's a copy of that creature, except it's a colorless artifact. (It's not a creature.)

Whenever Infernal Barrier is dealt damage, it deals 1 damage to each opponent.

Each opponent plays with the top card of their library revealed.
During each of your turns, you may play one card from the top of an opponents' library, and you may spend mana as though it were mana of any color to cast that spell.

{1}{W}, {T}: Other creatures you control get +1/+1 until end of turn.