MTG Wiki
Keyword Action
Introduced Theros
Last Used Forgotten Realms Commander
Reminder Text [cost]: Monstrosity N (If this permanent isn't monstrous, put N +1/+1 counters on it and it becomes monstrous.)
Storm Scale 4
30 cards
{W} 10% {U} 13.3% {B} 10% {R} 20% {G} 30% {R/G} 3.3% {G/W} 3.3% {G/U} 3.3% {artifact symbol} 6.7%
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Monstrosity is a keyword action introduced in Theros, where it is connected to the monster theme of the set. It is an ability that gives a power boost through a one-time payment.


Monstrosity is defined as giving the creature the ability to become monstrous. Monstrosity is an activated ability you can activate any time you can pay for it. When it resolves, it checks whether the creature is already monstrous. If it's not, the ability puts a number of +1/+1 counters on the creature and causes the creature to become monstrous.[1][2] Monstrosity skipped Born of the Gods, but reappeared in Journey into Nyx. It was reused in Commander 2015, Conspiracy: Take the Crown[3] and Modern Horizons.[4] It also appeared in Commander 2020, and was considered for Zendikar Rising.[5]

The Werewolf-to-Eldrazi of Eldritch Moon use double-faced card technology to portray a similar one-way transformation, albeit without the square stat change of +1/+1 counters. The Adapt keyword from Ravnica Allegiance is a tweaked version from Monstrosity that checks for counters rather than using an invisible marker.[6]


Monstrous is more like a characteristic of a card. Many creatures with a monstrosity ability have a triggered ability that triggers when the creature becomes monstrous. There are also some cards with monstrosity that gain abilities as long as they are monstrous.


From the glossary of the Comprehensive Rules (April 29, 2022—Streets of New Capenna)

A keyword action that puts +1/+1 counters on a creature and makes it become monstrous. See rule 701.31, “Monstrosity.”

From the Comprehensive Rules (April 29, 2022—Streets of New Capenna)

  • 701.31. Monstrosity
    • 701.31a “Monstrosity N” means “If this permanent isn’t monstrous, put N +1/+1 counters on it and it becomes monstrous.”
    • 701.31b Monstrous is a designation that has no rules meaning other than to act as a marker that the monstrosity action and other spells and abilities can identify. Only permanents can be or become monstrous. Once a permanent becomes monstrous, it stays monstrous until it leaves the battlefield. Monstrous is neither an ability nor part of the permanent’s copiable values.
    • 701.31c If a permanent’s ability instructs a player to “monstrosity X,” other abilities of that permanent may also refer to X. The value of X in those abilities is equal to the value of X as that permanent became monstrous.

From the glossary of the Comprehensive Rules (April 29, 2022—Streets of New Capenna)

A designation given to a creature whose ability including a monstrosity instruction has resolved. See rule 701.31, “Monstrosity.”


  • Although it is not a verb, it is considered a keyword action in the Comprehensive Rules
  • Once a creature becomes monstrous, it can't become monstrous again. If the creature is already monstrous when the monstrosity ability resolves, nothing happens.
  • Monstrous isn't an ability that a creature has. It's just something true about that creature. If the creature stops being a creature or loses its abilities, it will continue to be monstrous.
  • An ability that triggers when a creature becomes monstrous won't trigger if that creature isn't on the battlefield when its monstrosity ability resolves.


Example 1

Stoneshock Giant {3}{R}{R}
Creature — Giant
{6}{R}{R}: Monstrosity 3 (If this creature isn’t monstrous, put 3 +1/+1 counters on it and it becomes monstrous.)
When Stoneshock Giant becomes monstrous, creatures without flying your opponents control can't block this turn.

Example 2

Hundred-Handed One {2}{W}{W}
Creature — Giant
{3}{W}{W}{W}: Monstrosity 3 (If this creature isn’t monstrous, put 3 +1/+1 counters on it and it becomes monstrous.)
As long as Hundred-Handed One is monstrous, it has reach and can block an additional ninety-nine creatures each combat.

See also[]

  • Renown, a similar mechanic from Magic Origins
  • Adapt, a tweaked version of Monstrosity.[7]


  1. Mark Rosewater (September 2, 2013). "The Mechanics of Theros". Wizards of the Coast.
  2. Mark Rosewater (November 11, 2013). "Building a Better Monster". Wizards of the Coast.
  3. Shawn Main (August 15, 2016). "The Heart of a Conspiracy". Wizards of the Coast.
  4. Matt Tabak (May 31, 2019). "Modern Horizons Mechanics". Wizards of the Coast.
  5. Mark Rosewater (September 28, 2020). "Zendikar Rising Vision Design Hand-Off". Wizards of the Coast.
  6. Mark Rosewater (January 2, 2019). "Building Allegiances, Part 1". Wizards of the Coast.
  7. Mark Rosewater (December 19, 2018). "can simic stop getting uninspired +1/+1 counter mechanics pls?". Blogatog. Tumblr.