Hello community my name is Thehero7 and this is my katarina guide
In this guide i will tell u how to play katarina

Voracity
After a kill or an assist, Katarina gains 25 gold and her cooldowns are reduced by 15 seconds.

An amazing passive, allowing quick spamming of your spells and can turn a near death experience into one of the most amazing combos you've ever performed.

Bouncing Blade
Katarina throws a dagger that bounces from enemy to enemy, dealing magic damage. Each subsequent hit deals 10% less damage.

Cooldown: 9/8.5/8/7.5/7 seconds

Range: 600

Maximum bounces: 2/3/4/5/6

Magic Damage: 60/95/130/165/200 (+0.8 bonus Attack Damage and +0.35 per Ability Power)

A highly underestimated ability that has just been significantly changed. It now scales off AD and AP, making it better in both hybrid and AP builds, but the fact that it now only scales off bonus attack damage instead of all means a nerf to AD builds. Anyone who says Kat is all ultimate has not had a 450 per bounce dagger whirling round their team every few seconds. This should be your primary farmer early game, as well as your main harasser, even on AP for the first couple of levels. Simply stay back and last hit minions.

Tips
An enemy has just about escaped from you with no health? Damn thats a shame. Oh hey they are running past a line of minions. Just skip your blade up the minions and you've got one skillful looking kill. Bear in mind how many bounces your blades will do (max 6) and adjust which minion you target accordingly.

Killer Instincts
(Passive): Katarina's melee attacks and abilities deal increased damage.

(Active): Katarina's next ability has a bonus effect:
Bouncing Blade deals full damage to every target it hits and applies 50% healing reduction for 10 seconds.
Shunpo reduces incoming damage for 3 seconds.

Cooldown: 20/18/16/14/12 seconds

Damage Increase: 8/12/16/20/24

Damage Reduction: 15/20/25/30/35%

Also underestimated, it's hardly the greatest ability in the world, but 35% less damage is really nothing to be sniffed at. It's also great to chuck an instincts powered dagger at someone early game whos using a potion, or prevent that pesky Mundo/Warwick/whoever healing.

Tips
Activating this early and then using it just before it expires will maximize the effectiveness, as it's cooldown begins as soon as the ability is triggered.

Shunpo
Katarina instantly moves to her target's location. If the target is an enemy, she deals magic damage.

Cooldown: 10/9/8/7/6 seconds

Range: 700

Magic Damage: 80/120/160/200/240 (+0.75 per Ability Power)

This ability has a million uses. It can chase, finish off, fling you around like crazy as you leapfrog from dead foe to foe, escape from many situations, you get the idea. As an AP this will be your main nuke although not as much as before due to Bouncing Blades now scaling off AP too. However, I will point out that anybody who says Shunpo is a better nuker than Bouncing Blades is just silly. Bouncing Blades you can happily harass from distance, throwing them every few seconds doing 400 damage to every foe.

Shunpo you will probably use once or twice, and only when your actually in the fight. You wouldn't Shunpo to poke, you can poke for infinity with Bouncing Blades. Early game this ability can be used to farm, but only try and use it if you will definately not get the kill with Blades or an auto attack, and it won't land you in danger. You shouldn't be afraid to get close to an enemy (who doesn't have CC) though, as most people will run away if you Shunpo near them, even if it's just on a minion.

This is the key ability to Katarina, in the sense that it is key to using your ultimate. Learning when to Shunpo in and slice everyone is what will define you as a player. Always use Killer Instincts for this instead of Blades in a teamfight. Try and wait for the silences/stuns/whatever to be used. Use your initiative. Personally, I will often try and Shunpo in the middle of so many characters I can't be clicked on.

Tips
The most important thing to remember is what I call 'leapfrogging'. Shunpo refreshes instantly upon killing someone, so if theres a line of low hp enemy champions running away you can literally use each one to springboard to the next. Even if your Shunpo doesn't kill the person you target, it will often put you in range to throw a Bouncing Blade at a target futher away. Hopefully I'll get a video of this at some point, as it's difficult to explain.

Don't forget you can Shunpo to anything. It's pretty unlikely there will be a handy ward nearby but it's possible so remember it. It's also nice to play with a Teemo for this reason.

On of the best ways to escape is to Shunpo on an opponent running directly towards you and run in the opposite direction.

Try and play with people who understand how this ability works. So many times I have been running from a group of people eating my face, my ally is standing just outside Shunpo range, then he flees just before I teleport. Man that annoys me.

Generally you should be the last person to go into the melee of a teamfight, after all the abilities that can stop your ultimate have been used up. If your team are all dead by this point, at least your still alive. The chances are, if they have died that quickly you'd have been minced to.

Changes
This ability has now been changed so that it always lands on the opposite side of the target. This means that during the laning phase, your Shunpo is now a lot less useful for farming as it will put you in a position of more danger. However, it makes you very slightly better at escaping. Also, it makes you better for killing enemies. This is because it will give you a small amount more time to keep them in your Death Lotus, as you are now in between them and safety. It also means you can Shunpo then auto attack for a Lich Bane proc, whereas previously you could not reach them.

Death Lotus
Katarina goes into a state of extreme focus, throwing daggers with unrivaled speed at 3 closest enemy champions for 2.7 seconds.

Cooldown: 60/55/50 seconds

Area of Effect: 550

Daggers Thrown: 30 (Max: 10 per Champion)

Magic Damage: 40/50/60 (+0.55 bonus Attack Damage and +0.3 per Ability Power) per dagger

The key ability, positioning yourself with Shunpo is the hard part. Pressing R to disintegrate the opposition is much easier. It's important though to use this right, many players will Shunpo on a single target and then use Lotus as they run. This doesn't really work as they barely get hit. It works a lot better if the person is running towards you as it takes longer to run away. Because of her passive this ability seems to be up whenever you want it, and thats one of the things I love most about Kat. Have 2 characters you hit die in a teamfight and oh look there you go again.

Tips
It's also a very good defensive ability, even with multiple opponents at the base of a tower I will often Shunpo in and use it. This often scares them off, but do this with caution. Suicide is not advised.

You can block an escape route with it. your opponent is sandwiched between you and your team mates they have to choose to either go through them or the crazy whirling lady.

The stasis on Zhonya's Hourglass cancels Death Lotus in case you are wondering.

Greater mark of insight x9
Greater seal of potency x9
Greater glyph of warding x9
Greater quintessence of potency x9

These runes allows u to receive less dmg from the enemy(ap mid ofc) and with these runes u will be able to make great erly dmg and farming well too

My masteries are
21/0/9
Offering me a good ap addition for the start
a liitle bit more movement speed
and +duration on buffs

Good choices:

I always takeIgnite and Flash. I have seen many, many Ignite Exhaust Kats recently. This is a terrible, terrible build, stop doing it. Ignite OR Exhaust is fine, but Shunpo should never be your only escape, especially when you have to use it to jump in.

Exhaust - The main reason for this is to keep someone in your Death Lotus, although it loses a lot of use if you have Rylai's Scepter. You can also use this to blind an auto attacker if you need an emergeancy escape, but word on the grapevine has it the blind may be taken out soon.

Ignite - Net some early game kills, snowball away. How many times have you recoiled in horror as your opponent escapes with 1 hp, not with this you don't. Don't forget you can cast it during Death Lotus.

Flash - A flash/shunpo combo can escape from anything, and can be used to perform some outrageous towerdives. The combined reach of them is so huge you can be on top of a low hp enemy cowering under his tower before he can even move. If your feeling really brave, and want to dive on low hp, often you can shunpo in and then flash out. With regards to escaping, try and use shunpo first (unless you'll die), as you can use flash anywhere, and to get over walls.

Ok choices:

Ghost - I'd never take it myself, but ghost is always useful for catching up with people, and in certain situations can be better than flash for escaping (like when your running away from someone who has ghost too.)

Cleanse - Can be a life saver, but it can't stop your ultimate being interrupted so I don't use it.

Teleport - Just about makes it ok choices, but only for AD builds really. AD Katarina can rip a tower down in no time.

Bad choices:

Heal - If you need to use this, your going to die anyway.

Smite - Kat can't jungle.

Clairvoyance - Support ability.

Revive - Sigh

Clarity - Massive sigh.

PLEASE READ THE FOLLOWING BEFORE LOOKING AT THE NUMBERS. SOME VERY IMPORTANT INFORMATION.

Magic penetration is NOT conveyed in the figures here, but it will be included in the additional points. Bear in mind that if something has lots of magic penetration is numbers could potentially be much better than seemingly higher ones. Obviously I shouldn't need to say that the damage done will not be these exact numbers, as opponent's magic resist will reduce them. Runes and masteries will also not be shown (so for example in the additional notes you won't see the 15% magic penetration from your offense masteries). All damage is caculated using the spell's damage at level 18. All numbers are rounded, .5's are rounded down just in case. A variable figure represents stacking items such as Sword of the Occult or Soulstealer. Bloodthirsters are done seperately. Death Lotus damage is given per dagger.

Hybrid

Build 1 (Hexdrinker and Void Staff):

13729 gold
Bouncing Blade - 363-443 damage
Shunpo - 394 damage
Death Lotus - 205-260 damage

Additional points: 20% spell vamp, 20% lifesteal, 35% slow on cast, 15% movement speed increase on 20 stacks, 20 magic penetration, 40% magic penetration hexdrinker shield.

Build 2 (Bloodthirster and Void Staff):

15129 gold

]Bouncing Blade - 383-463 damage. 415-495 with Bloodthirster at max stacks.
Shunpo - 409 damage
Death Lotus - 218-273 damage. 240-305 damage with Bloodthirster at max stacks.

Additional points: 20% spell vamp, 35-45% lifesteal, 35% slow on cast, 15% movement speed increase on 20 stacks, 20 magic penetration, 40% magic penetration


Build 3 (Bloodthirster and Abyssal Scepter):

15484 gold

Same damage as build 2.

Additional points: 20% spell vamp, 35-45% lifesteal, 35% slow on cast, 15% movement speed increase on 20 stacks, 20 magic penetration, 20 magic reduction to surrounding enemies, 57 magic resist

AP

IMPORTANT: These numbers have not been updated since Deathcap was introduced. AP now does more damage than shown here, and boy does it show. You should have seen that team dissolve before my Death lotus in my last game, it was beautiful.

Build 1 (Void Staff):

14280 gold

Bouncing Blade - 357-427 damage
Shunpo - 560-605 damage
Death Lotus - 220-280 damage

Additional points: 15% reduced cooldowns on 20 stacks, 35% slow on cast, 20 magic reduction to surrounding enemies, 57 magic resist, 20 magic penetration, 40% magic penetration, zhonya's stasis

Build 2 (Lich Bane):

15455 gold

Bouncing Blade - 362-432 damage
Shunpo - 580-730 damage
Death Lotus - 224-285 damage

Additional points: 15% reduced cooldowns on 20 stacks, 35% slow on cast, 20 magic reduction to surrounding enemies, 20 magic penetration, zhonya's stasis, lich bane proc (for 462-662 damage), 87 magic resist, 7% movement speed incrase

A lot depends on your choice of build. On all builds you should be getting Blades first, to harass and to last hit. I see a lot of Kat's struggle to farm but I really don't understand how. Auto attacks deal with any minions close to you and Blades + Shunpo should mean you don't miss out on many futher away either. Be careful with your Shunpo now though due to the changes meaning you always land the opposite side of a minion. Even if your kept at a distance you have Blades. Often if I misjudge a last hit and get the minion to minimal hp with an auto attack I'll quickly Shunpo straight onto it to ensure I get it.

My choice of lane depends on the opponent. Kat can do perfectly well in both mid and side lanes. My personal opinion is that go mid unless there is a ranged carry there (ie Kog'Maw, Miss Fortune etc). A notable exception is Twitch, who you can kill very easily, especially since his most recent heavy nerf. That said, there are plenty of characters who have to go mid like Karthus, and since Kat is good in a side lane don't hog mid every game.

Mid

Concentrate on farming, but keep harassing with Shunpo (if AP or hybrid, Bouncing Blades is an obvious harass if your AD), especially after the opponent uses their harass spells. Take Vladimir. His Transfusion has a high cooldown at low level, Shunpo him every time he uses Transfusion and run back behind your minions. Obviously there are exceptions to this, like characters with stuns. Remember how many bounces your Blades are currently doing and try to hit the champion as any times as possible by bouncing it off minions, activating Killer Instincts whenever you think you will. Also use Killer Instincts and chuck one straight at them if they use a potion.

Work towards hurting them enough so that by level 6 a takedown is possible. If your hurt you can feign accidental suicide, straying a bit too close with low health, before Killer Instincts, Shunpo and Lotus. I always make sure to throw one Blade if I can before I Shunpo in. Maybe not immediately before, but a few seconds. If you feel you might not take them out, you can always Shunpo on them, flash a bit behind them then use Lotus so they stay in the area for longer if they head for the tower. Usually I've killed whoever is at mid before ganking but this doesn't have to be the case. Like most ganks it works best if the enemy have pushed your tower. You can Shunpo onto any minions behind them and Lotus to achieve the same effect as with flash described earlier. Do not forget about your passive, as it can often land you a double kill.

Side Lane

No different to mid really, except for working with your partner. Someone with a stun or snare is good for your Lotus. Morgana is basically the ideal partner, as she can both snare someone and shield you so your Lotus isn't interrupted. One of the main differences in a side lane is the brush. It's both an advantage and a disadvantage, depending on how you approach it. Make sure you are a person who turns it to an advantage. You be the main always hiding in the brush with a Lotus. You be the one constantly flinging daggers out from invisibility to last hit. Do not let your opponents do this.

Now for a a few list of characters you should pay special attention to.

Characters you do not want to lane against ideally:

Any character with a stun (snares are totally different, they don't stop Lotus).
Any character with a higher burst than you (ie Akali).

Characters you do NOT want to lane against in any situation:

Kassadin, LeBlanc, Katarina and Ezreal (built in flash renders your ultimate useless, although Kassadin is fine before level 6).
Malzahar (will obliterate you if you attempt to hurt them with Lotus).

As you can see these lists covers a damn lot of characters, and it is why Kat isn't considered totally viable in high level play. However the first lot aren't an insta loss situation, those are just slightly harder to face than others. List two you will probably die a horrible death if their not being played by idiots - gank a lot on other lanes or swap.

Characters you do want to lane against:

Characters who are convinced they can kill you before you kill them in a straight fight. Yes thats you Master Yi and Shaco.

Anyone squishy that doesn't fall into the above requirements. Namely *inhales*:
SOMETIMES Annie (wait until she has stun down)
Early Cho'Gath
Early Kassadin
Gangplank
Heimerdinger (will make your life hell until 6, before suddenly his smug face cowering behind his turrets is slashed to a pulp. Don't forget on his death his turrets die, don't fear them.)
Karthus (special mention to Karthus, he is prime prey. At level 6 there is basically nothing he can do to stop you wiping him out.)
Master Yi
Shaco
Soraka
Teemo
Early Tryndamere (will eat you after 6)
Twitch
Vladimir (it may not seem a good idea but bizarrely Kat is actually a very good Vlad counter if used correctly.)

A special mention quickly goes to stealth. Lotus can detect stealth by the fact it flashes on when a stealthed character nearby. The only situation where you should use it against a stealthed character however is against Akali. Use it in the middle of her bubble. Often if shes in the bubble during a fight shes in trouble and will probably die very swiftly.

I hope you've enjoyed my guide to Katarina, I'm pretty sure it's one of the most comprehensive out there and definately the only one that covers her reworked self in such complexity (as of the time of writing). If you have looked at this guide and thought 'yes, that build is for me!' then great, thats what I came here to do. Those of you who want to take more time to read through the figures in detail your in the same spot of bother as me. I have not decided yet on the build I am to play now after this patch (I'm caught between AP and Hybrid, I never use AD at level 30 as you die too easily) and the figures don't make one build clearly better than the others.

What I will say though, is Katarina is a fun and horribly underrated character whos just turned a significant corner. The problems stopping her being competitively viable are still there, but if anything shes been slightly buffed as an already powerful solo queuer. Please give her a try, and I hope you will fall in love with her as I did.