Hello. And welcome to my Katarina build.
The build is most to myself. I play after this build every times, and get good scores. Enjoy:)

Summary

- do not intiate a fight against equal teams.
- do not jump into the fight until your opponents have used their breaking abilities
- use the terrain [brushes ] around as often as u can
- use Death Lotus as often as u can
- use Killer Instincts and Bouncing Blade to harm your enemy over big distance

ABILITIES

Bouncing Blade - This is your main tool throughout the entire game. As it increases level, it deals more damage and increases the number of enemy units it can make contact with. You can use this to solo lane, farm creeps, or jungle. You want to get its ultimate effectiveness as soon as possible.
Killer Instincts - Aside from giving each use of other basic abilities extra effects, it also increases your base damage for every attack and ability passively.
Shunpo - This ability is not used for damage. This is either used to retreat (on ocassion go in any direction faster) and use just after to decrease the damage you receive while harrassing your enemies. It is mainly increasing survivability. Your allies can help you escape by knowing its range.
Death Lotus - Your ultimate can be highly devastating. It scales to 55% of additional attack damage. After your use killer-instincts and so use Shunpo (combo) you would use it. Beware though, that any enemy with a stun or silence of any form will completely interrupt this. Make sure it is timed well. You can also stay in brush, then jump out with Shumpo (if they are low) and use Death Lotus. Just make safe, your temates also attack them, or i think you will die. If they are low, are Death Lotus a good weapon to get kill with.




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Katarina's role in a game is simple - she's a ganker/finisher. She CAN carry for her team if she has a brilliant early game with a lot of kills and assists, but don't expect it every game.
More importantly, she CANNOT initiate for the team. You should never be the first person to engage the enemy team in a pitched 5v5 battle ala Malphite, your job instead is to sneak in unawares and quickly take out priority targets.

As the game progresses, you'll steadily gain more team presence as your ultimate increases dramatically in power, until eventually you'll be hitting as many as 3 enemies at once for tons of damage multiple times per battle.

Due to her fragile HP, Katarina should never be expected to tank for the team. Even so, you should expect to be targeted first in every battle due to how much of a nuisance you are. We will have to choose our items carefully so that we can survive the initial assault, as well as use Shunpo and Flash(if you choose flash instedt of ignite and exhaust) to back off if the heat gets too much.

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Spells

For my summoner spells while using the exceptional champion, Katarina, I take two highly offensive spells. Exhaust and Ignite for the following reasons. Exhaust can be highly useful as it can be used to slow enemies within the range of your Death lotus, it can be used to protect yourself from heavy enemy DPS and it can also be used to simply disable a target, rendering them useless and allowing you and your team to pick them off without a problem. As for Ignite, the reason why I take it is to help secure kills early in the game. Ignite can also be used in conjunction with Bouncing Blade to deal devastating damage to enemies who may already be within the range of their turret in a place where it will be dangerous to Shunpo to. Overall Ignite is a great spell as it suits Katarina's offensive nature and helps her get fed in the Early Game.
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Early Game - Level 1 - 9

In the early game just farm. Farm like there is no tomorrow for Katarina NEEDS to be farmed to be effective. Harass your enemies with Bouncing Blades and Shunpo. Around Level 6 you can go for a kill. If your partner has a stun, suppress or a slow you should EASILY pick up a kill.

Remember to stay in the brush and wait for your team mate to use their debuff on the target. Throw out a Bouncing Blade, Use Killer Instincts, Shunpo to the enemy and... well... Let the daggers fly! Unleash your Death Lotus on the enemy! Wow... A kill.. That was easy and the best part is, there will be plenty more to come!

Mid Game - Level 10 - 16

During the Mid game you should be farmed, fed and ready for battle. You and your team mates will annihilate the enemy in this part of the game. Make sure to jump into team fights when the enemy is busy fighting your team. This will ensure that you do not get targeted!

The Mid game, just like the Early game, is what will either make or break Katarina. You HAVE to succeed in this part of the game otherwise your power diminishes and your usefulness in battles does too.

Late Game - Level 17 +

Late gamet. Your performance in the Late game will depend on how you did early on. If you fed hopelessly, well, then you will generally continue to fail. There is not much you can do in this situation except for go and take care of the big minion waves.

However, if you did brilliantly before, you should continue to do so! Dominate the other team. Become godlike! Hear "LEGENDARY!" after every kill! All a fed Katarina has to do is win. That is all that should be left for you to do. Enjoy the glory and praise of your team mates and make sure to spread the word about this guide. xD

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Hope you enjoy my build, and you get some good games with it. I do.