Anti-Airing
There are many ways to jump and there are many ways to anti-air attack a jump. Jumping is risky because the character cannot block during a jump and their movement is predictable. Let's dissect the three parts of a jump and what happens when characters get hit during each part.
The character remains on the ground for a very short amount of time before becoming airborne. This is the first part of a jump and is called pre-jump. The character cannot block and is completely vulnerable during pre-jump.
The third and final part of a jump is the landing part. The character has to completely recover from landing before they can move or perform an action. Like pre-jump, the character is completely vulnerable during landing. The rules of landing differ by game. In some games the character doesn't have landing recovery if they didn't attack in their jump.
The second part of a jump is the airborne portion. This is when jumping attacks are possible. What happens when a character gets hit airborne depends on the game.
In some games, the character is vulnerable after being hit out of the air and can be hit more times. This is called floating a character into a juggle.
In other games, the character is in a state called air reset after being hit out of the air and is invincible until they land.
Pre-jump and landing are considered grounded and getting hit during either isn't any different. You can get hit by a damaging grounded combo before and after a jump.
Getting hit airborne is different as many combos will not work because the character is floated, air reset, or in an awkward position in the air. You will see players jumping defensively to escape unfavorable situations because getting hit once out of the air is better than taking a multi-hit combo on the ground.
The most common anti-air attacks are attacks that hit above the character's head. The uppercut is a great anti-air because it has vertical range without extending the upper body too much.
Certain attacks can be very difficult to anti-air from the ground. Remember you can jump as well to hit your opponent with an air-to-air anti-air attack.
Good anti-airs minimize the size of your upper body. Some attacks do this so well that they go under high attacks. This is called low profile. An attack that goes over low attacks is called high profile.
If you're playing a short character, you may be able to walk under your opponent to avoid their jumping attack. This is called a cross-under. If you're quick enough you can hit your opponent during their landing and/or before they turn around.
The King of Fighters Anti-Air Triangle
Most anti-air attacks hit descending jumps, but do not neglect anti-airs that hit characters as they're ascending. This is most common against jumps that are close and/or are lower to the ground. Close jumps are very common in The King of Fighters because the game has short hops. There is an interesting anti-air triangle in The King of Fighters games.
If the jumper attempts a close jump in, the defender can preemptively anti-air it with a jab.
If the jumper predicts the defender will whiff jabs, they can low profile under them with a low attack.
If the defender predicts the jumper will use a low attack, they can jump over it with their own jumping attack.
Don't forget that you can dissuade your opponent from jumping with positioning. Create distance to make their jump in whiff. Or close the distance where you can anti-air them as they're ascending.
I don't have a training mode exercise for anti-airing because I don't believe it's possible to get better at them in training mode. Jump ins work because they happen when you least expect them. It's like if I had the hiccups and told you to scare me to get rid of them. Because I'm expecting you to scare me, I'm not going to get scared. If I set the training mode dummy to jump at me, I'm going to anti-air successfully every time because I'm expecting it.
Air Blocking
Air blocking is a feature in many games. If a game has air blocking it's usually either an air dasher game where players spend a lot of time in the air. Or a game where offense is very powerful and air blocking keeps defense from being too weak.
You don't have to guess when air blocking because all attacks are blocked the same way. On the ground you have to decide between stand block or crouch block and if you guess wrong you get hit. In the air you either air block the attack or you don't. Jumping to air block to avoid high/low mixups is called chicken blocking.
In some games air blocking blocks all attacks.
In other games air blocking only blocks air attacks and gets hit by grounded attacks.
An attack that is specifically flagged to beat air blocking is called air unblockable. This is a confusing term because sometimes players call jumping unblockable attacks air unblockables.
There are drawbacks to air blocking. Air blocking has more pushback than blocking on the ground because the character is pushed backwards and downwards in an arc instead of just backwards. Players beat air blocking by forcing their opponent to air block multiple attacks to push them into the corner.
Another drawback is the attacker usually recovers before the defender after their attack is air blocked. On the ground, the defender usually recovers before the attacker after blocking an attack. This is because the defender has to fully recover from blocking the attack then land on the ground before they can perform an action.
Air Recovery
Almost every game with air blocking has air recovery. After getting hit out of the air, the defender has the ability to recover after they've left hitstun. Unlike recovering after a knockdown on the ground, air recovery is not necessarily considered disadvantageous for the defender. The defender can usually alter the direction and timing of the recovery to be unpredictable.
Air recovering backwards is the safest option as it leaves the characters far away from each other and allows the defender to escape pressure. It's the most common option but if the attacker expects this they can chase after the defender to stay close and leave them closer to the corner.
Air recovering forward is riskier as it may leave the defender right next to the attacker at a disadvantage. It's used when the defender doesn't want to put themselves closer to the corner. If the attacker chases too aggressively, the defender may recover over them and end up on the other side.
You might be wondering, "If air recovery is a thing how are air combos possible?" The defender does not immediately air recover, they can only air recover after fully recovering from hitstun. Air combos work because the character is hit again before they recover from hitstun. Players sometimes wait to anti-air their opponent so that they are close enough to hit them again with a fast attack before they recover from hitstun.
There's an obstacle every player has to jump over.