Hitstun and Blockstun miniguide

By OmegaRyuji

Introduction: Set your phasers to “stun”
When an attack makes contact with a character in a KOF game, that character will usually go into one of five states: blockstun (an attack was blocked), hitstun (an attack that does not knock down a grounded opponent), aerial reset (if the character was hit in the air with an attack that does not knock down), airborne juggleable (a special property of certain attacks that knock the opponent into the air and allow most attacks to connect afterwards), or knockdown (an attack that causes knock down hits). Each of these has certain strategic importance, but the focus of this article will be on the first two.

The “stun” part of the names blockstun and hitstun comes from the fact that these states greatly limit a character’s available options. In hitstun, a character is put through a reeling/hurt animation during which they are completely vulnerable to anything that the opponent tries to do (except normal throws and some other special cases), aside from in KOF XI, when the hit character can be switched out with a saving shift. In blockstun, the character is locked in a defensive animation during which they will continue to automatically block any further attacks that make contact, though the player still has to properly block attacks that can only be blocked standing or crouching, but has a few more options available.While in blockstun, the character can use up resources in order to guard cancel, with either a roll (GCAB), a standing CD attack (GCCD), or a tag (KOF XI only). The character can also alternate between a standing block for high or mid attacks or a crouching block for mid or low attacks.

General Notes and Exceptions: Always read the fine print
Note 1: In most competitive KOF games ,KOF XI being one of the exceptions, switching rapidly between standing and crouching guard will keep the character in a constant blockstun as long as they are not hit. For more information on this, refer to the tutorial article on throws and alternate guard by PhoeniX. It will not be discussed further within this article, but when considering applications of tick throws to your own play, keep in mind that all blockstun lengths in KOF games with alternate guard are technically only the minimum length, i.e. what will happen if the other player does not use alternate guard.

Note 2: Some KOF games, such as 98, allow a character to block in the air, under certain limitations. Since this is more the exception than the norm, it will not be discussed further in this article.

Note 3: In some fighting games, such as Garou: Mark of the Wolves, it is possible to exploit the fact that a character in blockstun will automatically block any more attacks that make contact which restarts the blockstun animation to keep the opponent blocking until either time runs out or the opponent’s guard is broken. Perpetually keeping a character in blockstun is known as “block lock.” This is of limited application in competitive KOF games, due to the pushback that the attacker goes through upon having an attack blocked and the defender’s option to use a guard cancel, and so is a very character-specific tactic that will not be discussed further in this article.

Stun Animation Lengths: Not even KOF escapes from Newton’s 3rd Law
In general, hitstun and blockstun animation lengths are standardized in KOF games as follows:

Standing or crouching light attacks (A or B): 11 frames hitstun, 9 frames blockstun
Standing or crouching heavy attacks (C or D): 19 frames hitstun, 17 frames blockstun
Standing or jumping CD: knockdown on hit, 21 frames blockstun
Jumping light attack: 11 frames hitstun, 9 frames blockstun
Jumping heavy attack: 11 frames hitstun, 17 frames blockstun
Command normals (e.g. Iori’s f+A), special moves, and DMs: 19 frames hitstun, 17 frames blockstun

Note that certain attacks do alter these numbers, such as Leona’s rdp+K in KOF 2002.

Also, these numbers are not necessarily applicable to KOF XIII, especially since some frame data, such as hitstun from jumping attacks, is changing in the console version.

General Advantages of Hitstun and Blockstun: DarKaoZ says, “Ash = I’m not going to hit you *hits the opponent* Oops, I did!”
The main advantage of hitstun is fairly straightforward. The character is completely vulnerable to anything except for normal throws, and hitting with anything will either restart the hitstun animation, cause an airborne juggleable state, or cause a knockdown state. Hitstun is the basic reason why combos work, where subsequent attacks after the first all make contact while the opponent is unable to defend.

Alternatively, the attacker can choose to time an attack to hit shortly after hitstun expires, forcing the opponent to react or guess correctly or take a hit which, ideally, will lead into a new combo. Basically, this is a choice by the attacker to go into a gamble that can lead to more damage upon success, which is known as a “reset.” A common set up for a reset is to hit an airborne juggleable opponent with something that causes as aerial reset state. This is usually the most versatile form of a reset since the attacker can run under the opponent just before they land to attack from the other side, and since a character in an aerial reset state is invulnerable to most attacks with the exception being attacks with the “anywhere juggle”/“ultimate juggle” property, so the attacker can time an attack to hit meaty right as the opponent recovers from the aerial reset. For more information on frame advantage and meaty attacks, refer to the tutorial article on reading frame data.

Of course, not every attack will lead into a combo. In these cases, the attacker should generally at least be using attacks that recovery quickly enough to give a frame advantage, keeping in mind that hitstun is usually longer than blockstun. In the best case, the attacker will have enough of an advantage to put the defender into a guessing situation with minimal gap for an invincible counterattack. Similar to a reset, this is known as a “mix up.” Examples of mix ups are to make the defender react to either a high or low attack, to make the defender react between an attack or a tick throw (discussed further below), or to attempt a frame trap (for more information on frame traps, refer to the tutorial article Reading Frame Data.) At worst, the attack should at least leave the attacker safe after hitstun ends, since otherwise, it would only make sense to use the attack as a surprise to finish off the defender’s remaining health.

Blockstun is slightly different yet similar at the same time. Obviously, it is not possible to combo off of blockstun, ignoring the possibility of connecting with an unblockable attack during blockstun, since this does not come up often in the competitive KOF games, but as with hitstun, the attacker can exploit frame advantage to put the defender into a mix up or can use the blockstun and pushback to reset the state of the match to a safe neutral situation. As with hitstun, it is generally not a good idea to use attacks that would leave the attacker unsafe after blockstun, meaning enough frame disadvantage to be vulnerable to punishment.

One of the typical applications of blockstun to set up a mix up comes from the fact that a character usually recovers from projectile attacks while the projectile is still active on screen. A common tactic after a knockdown is to put out a projectile attack that the defender will have to block as they rise. The idea behind this is that, unlike forcing the defender to block a meaty attack, the attacker will have gone through the entire recovery animation before the defender has blocked the projectile, giving the attacker the full 17 frames of blockstun to set up whatever they want to do, while also being safer against the chance of the defender doing an immediate attack upon rising.

Another common set up for a mix up out of blockstun is to make the defender block a jumping CD as late as possible. The attacker will recovery upon landing, while the defender will still have to go through most of the blockstun animation. This results in similar frame advantage to the above example, since the blockstun for a CD attack is normally 4 frames longer than for a projectile, which, with proper execution, will offset the additional time it takes for the attacker to land and recover.

Block Strings: I’m coming at your base with two rockvees and an ambo
If you look into pretty much any character’s frame data, you will find that most of their attacks are not going to leave them at a positive static difference. While this does not inherently make those attacks unsafe on block due to pushback and the defender’s counterattacks also having startup time, it is rarely a good situation to be at a frame disadvantage in close enough quarters for the defender to be able immediately retaliate with cl.C or cl.D, typically the fastest normal for a character in KOF. In order to make cancelable attacks safe, or at least safer, on block, it is common to cancel into further attacks to either end up at a frame advantage or to push the defender back enough that only relatively slow attacks will be able to reach, thus essentially nullifying a slight frame disadvantage. Intentionally doing a series of attacks against a blocking opponent is known as a “block string.”

For instance, in KOF 2002, Yashiro’s cl.D has a static difference of -8, and his f+A has a static difference of -9. Worse yet, both attacks leave him close to the defender; f+A actually moves him in closer, rather than pushing back, and thus quite vulnerable to being punished if he stops there. However, he can cancel into hcf+A~qcf+A, which has fast enough startup time that it will make contact before the blockstun from f+A ends thus leaving no gap for even an invincible move or command counter from the defender) and has a static difference of 0, making the entire string safe on block.

Keep in mind that block strings do not necessarily have to have no periods between the blockstun of one attack ending and the active frames of the next attack making contact, known as a gap. Frame traps are a special form of block string as well. The important part is for the entire sequence to leave the attacker safe while encouraging the defender to simply wait it out either because trying to squeeze in an attack will result in a counter hit or because there is simply no gap to do anything but block.

Also, remember that no block string in KOF is 100% faultless if the opponent has the resources to guard cancel. Recklessly doing block strings, no matter how safe based on static difference, will result in getting punished by guard cancels.

As a way of countering this, the attacker can use “staggered block strings.” A staggered block string is a series of attacks, usually fast light attacks, that is intentionally NOT done at the maximum possible speed. Gaps are left to accomplish two things: giving the attacker a chance to walk forward slightly between attacks in order to maintain close quarters, and to bait the defender into doing a roll or CD attack as a mistimed attempt at guard canceling that can then be punished appropriately. However, staggered block strings are usually not also ideal frame traps, i.e. the gaps will be large enough for the defender to put out a quick attack without risking being counter hit, so they have their own risks.

Tick Throwing: The oldest trick in the book
For most characters in any 2-D fighting game, low attacks are suboptimal for starting combos, and high attacks either have to be done from a jump or a hop in KOF or with a command normal that often requires further resources to combo after, such as max mode canceling in KOF 2002 or activating HD mode in KOF XIII, both of which have a startup period that can usually be reacted to by the defender. Because of these points, one of the tactics that has been in fighting games since the original Street Fighter 2, is tick throwing.

A tick throw is when the attacker does something which leaves them at frame advantage and then throws the opponent as soon as they are able to. This can be rather useful in KOF, where the best combo starters (often one of cl.C, cl.D, or cr.C) also tend to have very short start up, meaning the defender has a small window of time to react. For instance, in KOF 2002, Chris’s cr.A has a static difference of +2 frames, so after having that blocked, he has the option of doing an immediate cl.C or cr.C, which will frame trap with a 2 frame gap and can also lead into a further mix up beyond the scope of this article. Doing a delayed cl.C or cr.C as a staggered block string that can lead to further mix ups, or doing a delayed throw usually with D for the hard knockdown property, see below for why the delay is necessary.

It is important to keep in mind that after a character goes through a blockstun animation, they cannot be hit with any throw until 10 frames after the blockstun ends (note that this number might be different in KOF XIII). Attempting a normal throw either during blockstun or during the 9 frame period afterwards will result in a cl.C or cl.D attack instead, and a command grab will simply miss. The same applies to hitstun, except that command grabs will work as long as the hit character is still in the grab’s range. There is no actual mix up in that case, and the attacker would be better off doing something different to continue with the above Chris example, perhaps making the defender react to either a cr.B or instant hopping D would be better for an immediate mix up.

Because of the period of throw invincibility after blockstun, the set ups for tick throws in KOF have to be varied with other mix ups, otherwise the defender can learn to react to a particular set up by doing something before the throw invincibility period expires, most simply, throwing the attacker first. For instance, a common tactic with Chris is to use his hopping CD attack to put the opponent into blockstun for a mix up, as mentioned earlier. One way to add in the potential to tick throw is to sometimes use a slightly early hopping B instead for its much shorter blockstun so that the gap between the hop attack and the throw attempt is minimized. Once the defender grows used to this, Chris can then begin a further mix up by doing another hopping attack after the first one, avoiding the defender’s throw attempt by being in an aerial state or by doing a cr.B or cl.C timed to hit after the blockstun from the hopping B ends, aiming to hit during a possible gap between the end of blockstun and the defender’s throw attempt, just to show a couple of examples. After the opponent learns to respect those options as well, the tick throw starts to become viable again.

Of course, everything about tick throwing can also apply to command grabs like Clark’s hcf+K, which is usually more rewarding than using a normal throw at the risk of getting a whiffed grab animation if missed instead of a heavy attack.

Tying Things Together: This is what I’d call a…stunning conclusion
Essentially, the purpose of hitstun and blockstun is to reward the attacking player for making contact, either by allowing for a combo, by putting the attacker at frame advantage to allow for a mix up, or by leaving the attacker safe from retaliation. Actually utilizing this to build up an offensive game plan is where players can put their own personal flair into the game.

While most characters have some sort of flexibility in terms of how to approach being offensive, some are even best suited by significantly altering their approach based on the match up. There will obviously be some characters who are better suited for attacking with flurries of mix ups and/or resets, some who excel at setting up frame traps to fish for counter hits, and some who want to keep pushing the opponent out to avoid getting into a close quarters situation as much as possible and so forth. Considering how your characters of choice are best able to exploit hitstun and blockstun is important for being able to maintain offensive momentum with minimal risks. Going about developing this game plan is an art in itself, generally best learned through experience, and it’s one of the starting points for going from simply putting out random attacks while hoping for the best to actually playing KOF.


  • Very nice article OmegaRyuji, thanks. You are really breaking down the basic concepts that everyone needs at all stages.

  • Glad you found it useful. I think having a firm understanding of the basic concepts is an important thing for all players, plus doing articles like this helps me check my own knowledge.

    Haven’t got any more planned, but if anyone has something that they’d like me to write about, feel free to send me a PM suggesting it.

  • “Note that certain attacks do alter these numbers, such as Leona’s rdp+K in KOF 2002.”

    Some moves do alter these numbers. But Leona’s rdp+K is not one of them. On hit it does 19 frames of hitstun, on block it does 17 frames of blockstun. The difference is that Leona’s rdp+K has a different recovery on hit (4 frames recovery) than on block (30 frames recovery).

    Whip is a good example. Her cl.D for example does 27 frames of hitstun and 25 frames of blockstun , that’s why she can combo her cl.D into f+A (and her close C can’t) series despite f+A having 19 frames of startup.

    This ‘extra stun’ is done by making the hitstop on Whip smaller than on the opponent. The opponent undergoes the regular amount of hitstop (11 frames), while whip has less hitstop, that’s also why the timing of the cancel of that move is a bit weird (less time to buffer).

  • Good catch. I’d put that in tentatively when I was writing it up and completely forgot to check if it was right later. Hadn’t expected heart attack to have three different sets of frame data *laughs*

  • these numbers are not necessarily applicable to KOF XIII, especially since some frame data, such as hitstun from jumping attacks, is changing in the console version.

    Anyone know if there is a mook coming out with such data for kof13.

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