msem-instigator

Mill X cards. Then you may return a creature card with mana value X or less from your graveyard to the battlefield.

Advance {3}{W} (Cast this for {3}{W} to advance it as it enters. {3}{W}: Advance this as a sorcery.)
At the beginning of your upkeep, you gain 1 life.
Whenever Plush Tea Party advances, create a token that's a copy of it.

Reveal up to four cards you own from outside the game with the same name, then shuffle them into your main library.
Draw a card.

Whenever Poignant Hydra deals combat damage to a player, put a +1/+1 counter on it.
Creature spells you cast with power less than Poignant Hydra's power cost {1} less to cast.

You may cast cast up to two target instant and/or sorcery cards with total mana value 6 or less from your graveyard without paying their mana costs. If a spell cast this way would be put into your graveyard, exile it instead.
Exile Pointer Churn.

{B}{G}, {T}, Remove a -1/-1 counter from a creature you control: Create a 1/1 green Elf Druid creature token.

Whenever a player gains life, that player loses 2 life.

{T}, Exile a land card from your hand, from your graveyard, or a land that you control: Add one mana of any color.

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.

This spell can't be countered.
Polis's Demise deals 5 damage to each creature. Destroy all artifacts.

Whenever a land enters under an opponent's control, that player loses 2 life and you gain 2 life.

Changeling (This card is every creature type.)
{T}: Add {C}.

When Polytheism enters, return up to four target permanent cards not named Polytheism from your graveyard to the battlefield. They become 4/4 God creatures in addition to their other types.
Gods you control have indestructible.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever you cast an instant or sorcery spell, up to one other target creature has base power and toughness 0/2 until end of turn.

({T}: Add {W} or {U}.)
Pool of Light enters tapped unless you control a basic Plains or a basic Island.

As Port Town enters, you may reveal a Plains or Island card from your hand. If you don't, Port Town enters tapped.
{T}: Add {W} or {U}.

Counter target spell unless its controller pays {2}.
Wanderlust — If that spell has mana value 2 or less and you control four or more differently named lands, counter that spell.

Flying
Play with the top card of your library revealed.
Spells cost {X} more to cast, where X is the mana value of the top card of your library.

[+1]: Create a 1/1 green Merfolk creature token.
[0]: Target artifact or creature loses all abilities and becomes a green Seal creature with base power and toughness 3/3.
[–6]: Up to five target noncreature permanents lose all abilities and become green Merfolk creatures with base power and toughness 1/1.

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.

At the beginning of your upkeep, exile the top card of each of your libraries.
Put X cards exiled with Possibility Matrix on the bottom of their owner's library: You may cast a nonland card exiled with Possibility Matrix with mana value X or less without paying its mana cost.

At the beginning of each upkeep, if it's an extra turn, end the turn.
If a player would search a library, that player searches the top four cards of that library instead.

Flash
Flying
When Powder Scatterer enters, exile target noncreature spell. Its controller draws a card.