msem-instigator

({T}: Add {W}.)
Wanderlust — Otherworldly Plains enters tapped unless you control four or more other differently named lands.
{1}, {T}: Add one mana of any color.

({T}: Add {B}.)
Wanderlust — Otherworldly Swamp enters tapped unless you control four or more other differently named lands.
{1}, {T}: Add one mana of any color.

Vigilance, lifelink

When you're dealt damage, sacrifice Paracosm.
{T}: Add one mana of any color.

Whenever you create one or more tokens, scry 1.
{3}{U}, Sacrifice Pathshaper Mage: Aetherize target creature you control. Activate only as a sorcery. (To aetherize, create a token that's a copy of it, then exile that token.)

Untap all artifacts you control during each other player's untap step.
Tap two untapped artifacts you control: Target player mills two cards.

[+1]: You may play an additional land this turn.
[–1]: Discard a card. If you do, return target creature, land or sorcery card from your graveyard to your hand.
[–5]: Create Thrice-Folded Lotus, a colorless Masterpiece artifact token with “{T}: Add three mana of any one color.” and “{3}, {T}: This artifact deals 3 damage to any target.”

When Phantom Threader enters, create a white Aura enchantment token named Spectral Whispers attached to target creature. The token has enchant creature and “Enchanted creature has double strike as long as you control it. Otherwise, it can't attack or block.”

When Phasmopillar enters, search your library for a creature card with mana value 5 or greater, reveal it, put it into your hand, then shuffle. If a creature card with mana value 9 or greater was revealed this way, put two +1/+1 counters on Phasmopillar.

Whenever a source you control deals damage to an opponent this turn, exile the top card of your library. You may play it this turn.

{B}, {T}, Sacrifice Planar Eulogist: Aetherize target creature card in a graveyard. (To aetherize, create a token that's a copy of it, then exile that token.)
{6}{B}: Aetherize target creature card in a graveyard.

For each pair of basic land types, create a tapped colorless land token of those types. (The basic land types are Plains, Island, Swamp, Mountain, and Forest.)

Aetherize up to two target permanents you control. (To aetherize, create a token that's a copy of it, then exile that token.)

When Polgek Artisan enters, create an X/X colorless Juggernaut artifact creature token, where X is the number of artifacts and enchantments you control.

When Polgek Restorationist enters, you may return target artifact, enchantment, or planeswalker card from your graveyard to your hand.

Whenever Polgek Songcrafter attacks, other attacking creatures you control get +1/+0 until end of turn. If you control five or more attacking creatures, choose up to one target creature the defending player controls. That creature can't block this turn.

Whenever Portal Inhibitor attacks, exile target nonland card from defending player's graveyard. Copy it. You may cast the copy. (You still pay its costs, including color. Copies of permanents enter as tokens.)

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.

When Possibility Scope enters, search your library for a land card, exile it, then shuffle.
{T}: Target land you control becomes a copy of a land card exiled with Possibility Scope until end of turn.

You may put a card you own from outside the game into your hand. Add {B}{B}. You may cast only one more spell this turn. Exile Power From Beyond.

When Powercell Cultivator enters, create a tapped colorless Powercell artifact token with “{T}: Add {C}.”
Artifacts you control have “{T}: Add one mana of any color.”

When Powercell Engineer enters, create a tapped colorless Powercell artifact token with “{T}: Add {C}.”

Precursor Sanctum enters tapped. When it does, look at the top three cards of your library, exile one face down, then put the rest on the bottom of your library in any order.
{T}: Add {C}.
{4}, {T}: You may play the exiled card without paying its mana cost. Activate only as a sorcery.

Experience (Whenever this creature attacks, if it has fewer than three +1/+1 counters on it, put a +1/+1 counter on it.)
Whenever Primal Ruffian attacks, if it has a +1/+1 counter on it, other creatures you control get +1/+1 until end of turn. (If it had no counters on it when it attacked, this ability does not trigger.)

Flash
When Prismatic Champion enters, create a white Aura enchantment token named Sunward attached to target creature. The token has enchant creature and “Enchanted creature has protection from creatures.”