msem-instigator

When Possibility Engine enters, exile the top two cards of your library.
Wanderlust — During each of your turns, if you control four or more differently named lands, you may play a card exiled with Possibility Engine.

As an additional cost to cast this spell, pay {2} or reveal an instant or sorcery card from your hand.

({T}: Add {B}, {R}, or {G}.)
Primal Dominion enters tapped.

Flying
{3}: Prismscale Dragon gets +1/+1 until end of turn for each color of mana spent to activate this ability.

({T}: Add {G}, {U}, or {R}.)
Pristine Dominion enters tapped.

If Professor Haldean would leave the battlefield, exile him instead.
Whenever you cast a spell, you may untap Professor Haldean and another target permanent.
{T}: Professor Haldean deals 1 damage to each opponent.

Target creature you control fights another target creature.
Each player draws a card.

At the beginning of combat on your turn, target creature you control explores three times. It attacks this combat if able and other creatures you control can't attack this combat. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on that creature, then put the card back or put it into your graveyard.)

As Publishing Press enters, you may exile a nonland card with mana value 2 or less from your hand.
At the beginning of your upkeep, you may cast a copy of the exiled card without paying its mana cost if the spell's mana value is 2 or less.

Pyrophoric Blast deals 3 damage to target creature. If that creature would die this turn, exile it instead.

Target creature can't be blocked this turn. It explores. (Reveal the top card of your library. Put it into your hand if it's a land. Otherwise, put a +1/+1 counter on that creature, then you may put that card in your graveyard.)

Enchant creature
When Ravage of Moments enters and at the beginning of your upkeep, put a -1/-1 counter on enchanted creature.

Death knell — You may sacrifice a nontoken creature. If you do, create a 3/3 black Spirit creature token. (As a creature you control dies, trigger one death knell of that creature or another permanent you control.)
Creatures you control dying causes their death knell to trigger. (In addition to the normal death knell trigger.)

You may have Reaping Willow assign its combat damage as though it weren't blocked.
{2}{G}: Reaping Willow gains indestructible until end of turn.

Tap up to three target lands. They don't untap during their controller's next untap step.
Agonize (You may cast this card from your graveyard by putting a -1/-1 counter on a creature you control in addition to paying its other costs. Then exile this card.)

Exile the top three cards of your library. Until the end of your next turn, you may cast nonland cards exiled this way.
{3}{U}{R}: Return Reckless Experiment from your graveyard to the
battlefield tapped and transformed.

Flash

Flash
{1}, {T}: Scry 1.

Flash
When Remnant Spotter enters, put target permanent card from your graveyard on top of your library.

When Renatured Vines enters, draw a card and create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)
Renatured Vines power and toughness are each equal to the number of cards in your hand.

Whenever a creature enters, each opponent loses 1 life.

Tap up to two target creatures.
Draw a card.

Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Enchant creature
As long as enchanted creature has toughness 3 or less, it can't attack or block.

Codex — Ser Wayver, the Broken Hour; Suzume Oshiruko; Aguri, Shadow of Doubt; Sukhar, Consort to the Dark; Chi Lee of the Underworld. (As this enters, conjure its contents into a shuffled face-up additional library.)
You may spend mana as though it were mana of any color to cast this codex's contents.