A lot of people associate combat damage with the end of the combat phase. While it’s true that the majority of the time, people move straight from dealing damage to doing stuff in the second main phase or passing the turn, there is still the rest of the combat damage step and an end of combat step to pass through. That means each player will get priority after damage is dealt but before any surviving creatures stop being considered “attacking” creatures.
Why does this matter? Well, if you attack me with a 6/6 creature and a 2/2 creature, and all I have to block with is my own 2/2 creature, I can block your 2/2. When combat damage is dealt, I lose 6 life to your 6/6, then the 2/2s both die. Since attackers don’t stop being attacking creatures until we move through the end of combat step into the second main phase, now I can cast Dispense Justice targeting you, since you now only have one attacking creature to sacrifice (if I had cast it before damage, you would have surely sacrificed the 2/2 instead!).
For another example, let’s say I’m at 11 life, and you attack with 6 1/1 human tokens. For whatever reason, I want to make sure those creatures don’t untap next turn using Clinging Mists. If I cast it before damage happens, then it will prevent the damage this turn, but your dudes will untap next turn. However, if I take the damage, THEN cast Clinging Mists during the combat damage step (after my life total has been reduced to 5), I can lock all your attackers down. This leaves me free to alpha strike twice while all your creatures are tapped, and hopefully win the game before you get to untap your creatures again.
Thanks to Jason Lemahieu for this rules tip suggestion!
Today’s Rules Tip written by
Josh Stansfield, Level 2 judge from Orange, CA