Deathtouch

Whenever a Curse is put into your graveyard from the battlefield, return it to the battlefield attached to you at the beginning of the next end step.

At the beginning of your upkeep, you may attach a Curse attached to you to one of your opponents. If you do, draw two cards.

Flying

Whenever Maelstrom Archangel deals combat damage to a player, you may cast a spell from your hand without paying its mana cost.

Flying

Whenever Maelstrom Muse attacks, the next instant or sorcery spell you cast this turn costs less to cast, where X is Maelstrom Muse's power as this ability resolves.

Deathtouch, haste

Whenever Maestros Diabolist attacks, if you don't control a Devil token, create a tapped and attacking 1/1 red Devil creature token with "When this creature dies, it deals 1 damage to any target."

: Change the text of target spell or permanent by replacing all instances of + with -, and vice versa, until end of turn.

Flying

Unearthly Power — Instant and sorcery spells you cast cost less to cast for each creature token you control.

Blade of Magnus — Whenever Magnus the Red deals combat damage to a player, create a 3/3 red Spawn creature token.

: Draw two cards, then discard three cards.

, Sacrifice Magus of the Jar: Each player exiles all cards from their hand face down and draws seven cards. At the beginning of the next end step, each player discards their hand and returns to their hand each card they exiled this way.

, : Untap target artifact an opponent controls and gain control of it until end of turn. It gains haste until end of turn. When you lose control of the artifact, tap it.

When Mairsil, the Pretender enters the battlefield, you may exile an artifact or creature card from your hand or graveyard and put a cage counter on it.

Mairsil, the Pretender has all activated abilities of all cards you own in exile with cage counters on them. You may activate each of those abilities only once each turn.

Flying

Scavenge the Dead — When Malanthrope enters the battlefield, exile target player's graveyard. Put a +1/+1 counter on Malanthrope for each creature card exiled this way.

Flying, vigilance

When Malcator's Watcher dies, draw a card.

Flying

Whenever one or more Pirates you control deal damage to your opponents, you create a Treasure token for each opponent dealt damage. (It's an artifact with ", Sacrifice this artifact: Add one mana of any color.")

Partner (You can have two commanders if both have partner.)

, Sacrifice Malevolent Hermit: Counter target noncreature spell unless its controller pays .

Disturb (You may cast this card from your graveyard transformed for its disturb cost.)

When Manic Scribe enters the battlefield, each opponent mills three cards.

Delirium — At the beginning of each opponent's upkeep, if there are four or more card types among cards in your graveyard, that player mills three cards.

When Man-o'-War enters the battlefield, return target creature to its owner's hand.

: Manta Riders gains flying until end of turn.

Flying

: Add or .

Ward (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays .)

Islandcycling (, Discard this card: Search your library for an Island card, reveal it, put it into your hand, then shuffle.)

Flying, vigilance, ward

Whenever you commit a crime, surveil 2. This ability triggers only once each turn. (Targeting opponents, anything they control, and/or cards in their graveyards is a crime.)

Dethrone (Whenever this creature attacks the player with the most life or tied for most life, put a +1/+1 counter on it.)

Other creatures you control have dethrone.

Whenever a creature you control with a +1/+1 counter on it dies, return that card to the battlefield under your control at the beginning of the next end step.

Dethrone (Whenever this creature attacks the player with the most life or tied for most life, put a +1/+1 counter on it.)

Whenever Marchesa's Infiltrator deals combat damage to a player, draw a card.

Vigilance, trample

Whenever a creature you control deals combat damage to a player, draw a card if that creature has a +1/+1 counter on it. If it doesn't, put a +1/+1 counter on it.

Marjhan doesn't untap during your untap step.

, Sacrifice a creature: Untap Marjhan. Activate only during your upkeep.

Marjhan can't attack unless defending player controls an Island.

: Marjhan gets -1/-0 until end of turn and deals 1 damage to target attacking creature without flying.

When you control no Islands, sacrifice Marjhan.

When Marsh Crocodile enters the battlefield, return a blue or black creature you control to its owner's hand.

When Marsh Crocodile enters the battlefield, each player discards a card.

Woman Who Walked the Earth — When Martha Jones enters the battlefield, investigate. (Create a Clue token. It's an artifact with ", Sacrifice this artifact: Draw a card.")

Whenever you sacrifice a Clue, Martha Jones and up to one other target creature can't be blocked this turn.

Doctor's companion (You can have two commanders if the other is the Doctor.)

Whenever Marvo, Deep Operative attacks, clash with defending player. (Each clashing player reveals the top card of their library, then puts that card on the top or bottom. A player wins if their card had a higher mana value.)

Whenever you win a clash, draw a card. Then you may cast a spell from your hand with mana value 8 or less without paying its mana cost.

When Master of Death enters the battlefield, surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

At the beginning of your upkeep, if Master of Death is in your graveyard, you may pay 1 life. If you do, return it to your hand.

Flying

Whenever Master of Predicaments deals combat damage to a player, choose a card in your hand. That player guesses whether the card's mana value is greater than 4. If the player guessed wrong, you may cast the card without paying its mana cost.

Morph (You may cast this card face down as a 2/2 creature for . Turn it face up any time for its morph cost.)

When Master of the Veil is turned face up, you may turn target creature with a morph ability face down.

Flying

When Master of Winds enters the battlefield, draw two cards, then discard a card.

Whenever you cast an instant, sorcery, or Wizard spell, you may have Master of Winds's base power and toughness become 4/1 or 1/4 until end of turn.

, , Return an artifact you control to its owner's hand: You may put an artifact card from your hand onto the battlefield.

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for .)

When Maverick Thopterist enters the battlefield, create two 1/1 colorless Thopter artifact creature tokens with flying.

Flying

Multicolored creatures you control have flying.

As Meddling Kids enters the battlefield, choose a word with four or more letters.

Spells with the chosen word in their text box can't be cast.

Flying

Whenever Medomai the Ageless deals combat damage to a player, take an extra turn after this one.

Medomai the Ageless can't attack during extra turns.

Play with the top card of your library revealed.

You may cast instant and sorcery spells from the top of your library.

Whenever you cast an instant or sorcery spell from your library, copy it. You may choose new targets for the copy.

Heroic — Whenever you cast a spell that targets Meletis Astronomer, look at the top three cards of your library. You may reveal an enchantment card from among them and put it into your hand. Put the rest on the bottom of your library in any order.

Flying

, Return a land you control to its owner's hand: Create a 1/1 blue Illusion creature token with flying.

Flying

Whenever Meneldor, Swift Savior deals combat damage to a player, exile up to one target creature you own, then return it to the battlefield under your control.

When this creature enters the battlefield, you may draw a card.

Whenever Merchant Raiders or another Pirate enters the battlefield under your control, tap up to one target creature. That creature doesn't untap during its controller's untap step for as long as you control Merchant Raiders.

, : Draw two cards.

, , Discard a card: Mercurial Chemister deals damage to target creature equal to the discarded card's mana value.

Flying

Whenever Mercurial Kite deals combat damage to a creature, tap that creature. That creature doesn't untap during its controller's next untap step.

Mercurial Spelldancer can't be blocked.

Whenever you cast a noncreature spell, put an oil counter on Mercurial Spelldancer.

Whenever Mercurial Spelldancer deals combat damage to a player, you may remove two oil counters from it. If you do, when you next cast an instant or sorcery spell this turn, copy that spell. You may choose new targets for the copy.

Whenever a creature you control explores, Merfolk Cave-Diver gets +1/+0 until end of turn and can't be blocked this turn.

Flying

Whenever you cast a kicked spell, scry 2.

, : Target player mills two cards.

When Merfolk Observer enters the battlefield, look at the top card of target player's library.