msem-instigator

When Malicious Growth enters and at the beginning of your upkeep, put two +1/+1 counters on target land you control.
{1}{G}: Target land you control becomes a 0/0 Elemental creature with haste and vigilance until end of turn. It's still a land.

When Mana Rose enters, you gain 2 life and scry 2.
{1}, {T}: Add one mana of any color.

Menace
Experience (Whenever this creature attacks, if it has fewer than three +1/+1 counters on it, put a +1/+1 counter on it.)

Menace
When Marrow Raptor enters, you may sacrifice a land or exile a land card from your graveyard. If you do, put a +1/+1 counter on it.

Whenever a nonbasic nontoken land enters under an opponent's control, create a tapped colorless land token named Fading Rift with “{T}, Sacrifice this land: Add one mana of any color.”

When Matron of Machines dies, put a +1/+1 counter on up to one target creature.
{3}{W}, Exile Matron of Machines from your graveyard: Create two 1/1 colorless Construct artifact creature tokens. Activate only as a sorcery.

Trample, hexproof
When Maw of a Thousand Worlds enters, distribute X +1/+1 counters among creatures you control, where X is the number of differently named lands you control.
When Maw of a Thousand Worlds dies, you may remove any number of counters from among permanents you control. For each counter removed this way, draw a card.

When Meteor Harbinger enters, choose one —
• Meteor Harbinger deals 2 damage to each creature.
• Each player sacrifices two lands.
• Meteor Harbinger deals 2 damage to each of two target players or planeswalkers.

Flash
Wanderlust — When Microzoologist enters, search your library for a creature card with mana value 1. If you control four or more differently named lands, you may search for a creature card with mana value 3 or less instead. Reveal that card, put it into your hand, then shuffle.

Sabotage — Whenever an opponent or permanent an opponent controls becomes the target of a spell you control, put a +1/+1 counter on Mirrorcast Battlemage.
Remove three +1/+1 counters from Mirrorcast Battlemage: Copy target instant or sorcery spell you control. You may choose new targets for the copy. Activate only once each turn.

({T}: Add {B} or {R}.)
Molten Falls enters tapped.
{1}, {T}: Add {B}{B} or {R}{R}.

Lifelink
Whenever Morning's Warden becomes the target of a spell or ability an opponent controls, exile target creature that player controls.

At the beginning of combat on your turn, you may attach target Equipment you control to Nina, Master of Arms.
Whenever Nina attacks, the next artifact spell you cast this turn costs {R/W}{R/W} less to cast. (This can reduce the amount of generic mana you pay.)

Flash
When Notorious Smuggler enters, target opponent reveals their hand. Choose a nonland card revealed this way. Copy it. You may cast the copy this turn. (You still pay its costs, including color. Copies of permanents enter as tokens.)

Flying
Whenever Novaheart Dragon enters or attacks, you may take an extra turn after this one. If you do, you lose the game at the beginning of that turn's end step.

Flash
Whenever you cast an artifact or enchantment spell, put a +1/+1 counter on Observer of Secret Paths. It can't be blocked this turn.

{T}: You may put a land card from your hand onto the battlefield.
{1}, {T}: Aetherize target land you control. (To aetherize, create a token that's a copy of it, then exile that token.)

Whenever you cast a noncreature spell, Omegalomania deals 2 damage to any target. Whenever a permanent you don't control dealt damage this way dies this turn, return it to the battlefield tapped under your control.

When Opulent Proprietor enters, you may search your library and/or graveyard for an Aura, Aurashaper, Equipment, or Vehicle card, reveal it, and put it into your hand. If you search your library this way, shuffle.

{T}: Look at the top card of your library. If it's a land card, you may reveal it and put it into your hand.
Crew 2 (Tap any number of creatures you control with total power 2 or greater: This Vehicle becomes an artifact creature until end of turn.)

Reveal the top four cards of your library. You may put a creature or land card from among them into your hand. Put the rest into your graveyard.

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.