Once you’re down, your opponent will probably use that time to set you up for their next attack. It’s important that you know what to do when you’re knocked on your back to make it harder for your opponent.
Do nothing to stand straight up in place after a knockdown. This is the fastest way to get back up, but if you’re still close to your opponent, you will have to deal with their attack.
Press any button or tap back to roll backward out of harm’s way. This can put you out of range for your opponent’s next attack, or they can predict your roll and chase you down.
Hold down the "change stance" button to stay down after a fall to beat out preemptive attempts to set you up as you stand up. In the example you see here, Scarecrow anticipates the timing for a normal wakeup from Catwoman, but she stays down, and his jump-in attack hits air.
Some moves, like sweeps, lead to what we call a "hard" knockdown. This means you can’t roll out once they’ve landed and are effectively stuck in place.
When you do a move immediately upon standing up, you’ll see "Wakeup" appear on the screen. If you have a very fast special move or something that pushes through other attacks (like Deadshot’s meter burn flying knee), that attack might make a good wakeup.
Here’s a situation that comes up a lot when one player is down: One character jumps up over the other’s head, and they attack on their way down. The back of that character’s leg or knee smacks the other player in the head and they go down, even though they were holding back to block. What happened?
This is a consequence of the "hold back to block" mechanic. When the character crosses over above you and switches sides, the "back" direction is now reversed. The opponent looked like they were going to attack you from the left, but in fact they wound up attacking you from the right.
When an opponent jumps at you, anticipate the arc of their jump and, if they look like they’re going to pass over your head, switch the direction of your block. Sometimes this can be tricky to judge, which is the whole point of the cross-up: to confuse you.
To figure out your own cross-ups, experiment by jumping from different distances with different attacks. A lot of the air attacks in this game, especially Batman’s jumping heavy, the move we used to demonstrate here, are built to cross up.