Mutavault is back in town, and doing fun Mutavault things! It swings for 2, it gets pumped by Master of Waves, it has the subtypes of Ninja Mutant Turtle- and it taps for mana! What a land. However, some people don’t know how to properly attack with it! You see, to swing with your Mutavault, it has to be a creature when you start declaring attackers, which is the absolute first part of the Declare Attackers step. So, by-the-book, it needs to be a creature BEFORE that point. Your last chance to animate it so it can attack is during your Beginning of Combat Step.

If your opponent allows you to move to attackers, it’s too late to declare Mutavault as an attacker. You can’t try to apply out-of-order sequencing there like you can with blocking. However, if you go to combat, and the opponent takes an action in the beginning of combat step (like killing or tapping one of your creatures to make sure it can’t attack), you will get priority again and will be able to animate Mutavault in time to declare it as an attacker.