Skittering CrustaceanHow it works & interactions with other cards

Understanding Monstrosity

The monstrosity ability is a one-time activation that checks if the creature is already monstrous. When you pay seven mana, the game checks if Skittering Crustacean has the 'monstrous' designation; if it does not, it gains four +1/+1 counters and becomes monstrous permanently. Once it is monstrous, the secondary static ability activates, granting it hexproof for as long as it remains on the battlefield.

Step-by-Step Resolution

First, you activate the ability by paying six generic and one blue mana. This ability goes on the stack and can be responded to by opponents. If the ability resolves, the game checks if the creature is already monstrous. If it is not, you place four +1/+1 counters on it. Immediately after these counters are placed, the creature becomes monstrous, and the hexproof ability becomes active, preventing opponents from targeting it with spells like removal or bounce effects.

Common Mistakes

A common error is attempting to activate monstrosity a second time to get more counters. While you can technically pay the mana to put the ability on the stack again, it will do nothing upon resolution because the creature is already monstrous. Additionally, remember that hexproof only protects Skittering Crustacean from your opponents' spells and abilities; you can still target it with your own spells to further buff its power.

When to Activate

Timing is crucial because the creature does not have hexproof until the monstrosity ability fully resolves. If an opponent casts a removal spell in response to the activation, Skittering Crustacean can still be destroyed. The best time to activate this is when your opponent is tapped out or when you have enough mana to threaten a massive block or a lethal attack.

Interaction examples

Scaling the Board State

Solemn Simulacrum

You play Solemn Simulacrum to ramp into your seventh land. Once you have the mana, you activate Skittering Crustacean's monstrosity. It grows from a 2/3 to a 6/7. Even if your opponent has a removal spell ready for the Solemn Simulacrum, the Skittering Crustacean becomes a much larger threat that they can no longer target once the ability resolves.

Doubling the Crab's Potential

Roaming Throne

If you have Roaming Throne on the battlefield naming 'Crab', you might expect the monstrosity ability to trigger twice. However, monstrosity is an activated ability, not a triggered ability. Roaming Throne does not interact with the monstrosity activation of Skittering Crustacean, as it only affects abilities that start with 'When', 'Whenever', or 'At'.