msem-instigator

Destroy target artifact or enchantment. Its controller gains 4 life.

Destroy all nonland permanents with mana value 3 or less.

Players can't gain life.
Whenever a player casts a spell, Rage of the Ravaged deals 1 damage to that player.

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a legendary spell or activate an ability of a legendary permanent.

{T}, Pay 1 life, Sacrifice Wayfarer's Shrine: Search your library for a basic land card, put it onto the battlefield, then shuffle.

Repeat the following process X times. Exile a creature you control, then return it to the battlefield under your control.
Exile Lazaire's Conjuring.

Archive 5 (As this enters, shuffle the top five cards of your main library into a new face up library. Sacrifice this after the archived library is empty.)
At the beginning of your upkeep, put the top card of any of your libraries on the bottom of the archived library, then you may put any card in the archived library on top of the archived library.

Dawson's Collector can't block.
Whenever Dawson's Collector attacks, you may sacrifice another creature. If you do, create a tapped Treasure token.
Whenever you sacrifice your third permanent each turn, each opponent sacrifices a creature or planeswalker.

Flying, haste
{X}{R}{R}, Exile an instant or sorcery card with mana value X from your graveyard: Return Merkurio's Familiar from your graveyard to the battlefield. It gets +X/+0 until end of turn.

When Leija's Greenblade enters, you may pay {G}. If you do, destroy target artifact or enchantment.

Search your library for a permanent card with mana value 3 or less and put it onto the battlefield, then shuffle.
Motley — Then if there are five or more names among nonland permanents you control, you gain 7 life.

Trample
Assault {2}{R}{G} (Whenever this attacks, if it has no +1/+1 counters on it, you may pay its assault cost to put a +1/+1 counter on it.)
If one or more +1/+1 counters would be put on a creature you control, that many plus one +1/+1 counters are put on it instead.

Each other Rogue creature you control enters with an additional +1/+1 counter on it.
Remove a +1/+1 counter from a creature you control: That creature can't be blocked this turn.

Whenever you cast an instant or sorcery spell, you may have Xenocrata's Fleet become a 4/4 Ship artifact creature with haste until end of turn.
Whenever Xenocrata's Fleet deals combat damage to an opponent, create that many 1/1 red Warrior creature tokens.

{T}: Add {C}{C}. Spend this mana only to cast spells with mana value 5 or greater.

(As this Discovery enters and after your draw step, add a progress counter. Stop after you've discovered.)
I, II — Look at the top five cards of your library. Put up to one creature card with mana value 2 or less from among them onto the battlefield. Put the rest on the bottom of your library in a random order.
Discovery — At the beginning of combat on your turn, tap target creature an opponent controls.

Journey three times. (Exile the top three cards of your library face up. Whenever a creature you control deals combat damage to an opponent, put a journeyed card you own into your hand.)

Converge — Counter target spell unless its controller pays {1} for each color of mana spent to cast Cosmic Sinkhole.

Choose two —
• Destroy target artifact.
• Discard a card, then draw a card.
• Investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

When Atlas of Worlds enters, search your library for any number of land cards with different names and exile them, then shuffle.
You may play lands exiled with Atlas of Worlds.

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Each player mills three cards.
Draw a card.

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)
Create a tapped colorless Mountain Forest land token. (It has “{T}: Add {R} or {G}.”)

Civilized — Whenever Founding Hero attacks, if you control an artifact, a creature, and an enchantment, Founding Hero gains double strike until end of turn.

You may put a creature or Revelation card from your hand onto the battlefield. Exile that permanent if it would leave the battlefield. If it's a Revelation, it enters as a Horror creature.
Coalesce {7}{U}{U} (You may cast this from your graveyard for {7}{U}{U}. If you do, it enters as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)