This page is intended to document general strategies and counterplay against Katarina which can be adopted by any character. For more specific match-up tips, visit the Katarina section on your character's Matchup page.
Basic Counterplay Gameplan
Katarina gets her damage from your mistakes. If you press at the wrong frames, you will get CH-launched. If you whiff, you will get whiff-punished. The main way she induces mistakes from you is by poking or running mixups. She does not get a lot of reward from her pokes either in terms of damage or frames. Her mixups can be tricky to deal with (HAR) and somewhat rewarding (FC), but she cannot set them up easily from her pokes. The solution is to simply play patiently and turtle. Pressing according to frames will eliminate the possibility of getting CH-launched via frame traps and will force Katarina to try CH-fishing from neutral. She loses her turn completely after a failed CH attempt (e.g. after df+4), so this will allow you to run your own mixups. Playing patiently will also reduce the chances of Katarina sidestepping your moves into a whiff-punish. Reducing your own mistakes will force Katarina to poke you (to induce mistakes) or force HAR/FC mixups or risky lows to get damage.
Her poking lows are low damage and don't allow her to continue pressure, so you can afford to eat more lows than you think. A lot of her moves are linear or weak to SSR, so step right often when she's poking you down. React to and block her heavy lows for a full launch punish. Backdash out of range 1 to force her to approach to start her poking game and keep her out. Her approach tools are all linear (WR3, f,F+3) or risky (manual HAR, df+3+4).
If she's unable to force mistakes with pokes and movement, and unable to get enough damage from her poking, she will have to resort to HAR or FC mixups for raw damage. SSR duck beats nearly every option from HAR if she transitions into HAR through a blocked move. SWR against her FC mixups, but remember that ws3,3,3,3,3 might clip you after the first 3 hits.
Dealing with HAR
Katarina can enter HAR from a few key strings, or manually. HAR has limited utility as a mixup stance on paper, and with proper defence can be made very risky for Katarina to use for mixups, or reduced to serving only to make strings "safe" or to transition to FC.
When Kat enters HAR from a string, she will be either at +3 or -1. She is +3 from d+2,F or b+1,F (most common). She is -1 from 4,4,4,F (most common) or 3,3,3,F. The below section details options against the HAR transition in both cases, referring to the two cases as whether Kat is -3 or +1 upon entering HAR or as a '+3 transition' or '-1 transition'.
Side Step Right
SSR after 4,4,4 on block will evade all options from Harrier except HAR.df+2,3, allowing a punish if any Harrier moves are used, but gives up the option to punish 4,4,4. From b+1,F, HAR.1 will clip SSR. HAR.df+2,3 will get blocked, and the second hit of the string can be ducked and launched. This is the option you should default to when testing out an opponent, before cycling other options on a read. Make sure to practice it since reacting to the transitions is not that easy.
SSR~duck evades all HAR moves other than HAR.df+2,3 and ducks HAR.1, although a full launch punish on the latter is tough to execute after committing to an SSR + duck. HAR.df+2,3 will hit you if you SSR~duck, however. It is recommended to use this until Katarina starts using HAR.df+2,3 to track you, then revert to SSR~block.
Ducking or flash ducking will allow you to crush an immediate HAR.1 for a potential launch punish (flash ducking may only net you a standing punish). However, it leaves you vulnerable to HAR.4, and you will get hit by slower lows like HAR.3 or HAR.df+3. It is not theoretically possible to perfectly fuzzy guard the mixup since moves can be done at any time while Kat is in HAR, removing a set trigger for initiating the fuzzy guard.
Quick pokes like a jab or df+1 will hit Katarina out of any HAR move except for HAR.1. However, HAR.1 can CH you for 51 dmg. A single jab will be high crushed and punished (at -1) or CH (at +3) by HAR.1, while committing to a jab string will get counterhit in both cases. Not recommended unless you have a read.
Generic down jab
A generic down jab comes out at 10 frames so will punish 4,4,4 and also high crushes HAR.1 for either transition. This will beat everything except HAR.3, HAR.uf+3 and HAR.df+3, which will low crush and punish the d+1. Risk-reward is not in favour of this option, but it is useful to force Katarina to use the slower low-crush options which can then be jab-floated. A generic i12 d+4 also works similarly.
A single high with counterhit properties that is i12 or faster such as a magic 4 or King's b+1 has a very high potential reward on -1 transitions with relatively little risk. It will counterhit all HAR options except HAR.1, which will only connect as a normal hit, not counterhit. This is not true for +3 transitions, during which HAR.1 will always CH a 12f high.
Characters that have an i12 mid move, such as Feng (b+4) or Alisa (df+4) can use this to completely option-select the -1 HAR transition. This will not punish 4,4,4 on its own but will hit all options from the HAR transition, even HAR.1. However, HAR.1 will CH in case of a +3 transition.
The complete HAR mindgame
Against HAR transitions, it is generally better to use an i12 mid (-1 transition) if your character has one, or SSR+duck (+3/-1 transitions). This will force Katarina to use df+2,3 to catch you stepping. Now, mix in SSR+guard to bait df+2,3 for you to duck and launch-punish. At this stage, the mixup is in your favour.
To deal with your stepping, Katarina has two options she can add - delayed HAR moves or FC transition into a mixup. She is vulnerable to mids and lows during the animation. In the latter case, she is vulnerable to immediate mids as slow as i17 (-1 transition) or i14 (+3 transition) even with the FC transition into block done as fast as possible. Since it is not possible to react to this and do the mid, you must press pre-emptively, allowing you to be CH by immediate HAR.1 all over again. This brings us back to the first layer.
Dealing with common strings
|1,1,1||mid-mixup out of 1,1; safer CH-fishing out of 1,1||block and take your turn; can be parried with certain characters|
|1,1,2||high-mixup out of 1,1; to get plus frames (+7)||duck and launch; if blocked, backdash; can be parried with certain characters|
|1,1,3||mid-option out of 1,1; to get a better frame situation after 1,1||SSR and launch; jab-float|
|1,1,4||hard-read on ducking/interrupting to get a launch||block and launch punish; can be parried with certain characters|
|4,4,4,4,4||beginner magic 4 combo; oppressing opponents who can't deal with the string||duck the 4th hit and launch; can also SSR|
|uf+4,4,4,4,4,4||beginner hopkick combo||use i13 punisher after first two hits|
|df+3,3||as a chunky KND low||low-block the second hit and launch punish; can be blocked even if the first hit connects on CH|
|d+3,4||to discourage punishment on d+3; to create space via pushback||duck the second hit and launch; can be ducked even if first hit connects on normal hit|
|d+3,3||to discourage punishment on d+3; mid-mixup to d+3,4||block and punish; can be punished even if first hit connects on normal hit|
|b+4, 1+2||whiff punisher; to obtain slight plus frames; to discourage punishing b+4||duck and launch|
|b+4, 3+4||mid-mixup to b+4, 1+2; to discourage punishing b+4||block and punish|
|df+2,4||mid high, plus on block; tracks Kat's weak side||duck and punish; can SSR if df+2 hits off-axis to the right|
|df+2,2||mid-mixup to df+2,4||i10 punish; can SSR if df+2 hits off-axis to the right|