One of the best champs in the game, she has very strong skills and can easily carry a team. If Kat is not targeted down or cc'd to death she can and will win team fights for her team. Kat is a mid champ plain and simple she really has no reason not to take mid except for a few that I will mention later. She is a great harasser a great nuke and a great assassin aka nuke/ganker.
She is by far my personal favorite champ some of the scores that I've put up with her are 17 0 3 and 18 4 15 if you play smart you can and will die less and kill more just because that is how Kat is.
One thing I feel compelled to let everyone know you need to be confident with Kat for any of this to work if you aren't confident then don't mid you will ruin games by losing/feeding mid
Ashe- super squishy and doesn't start with a ton of damage so keep the harass up early if you don't get first blood you will have her so afraid to move away from her turret you should easily out level her.
Veigar- Sure he has a stun but if he doesn't hit you with it when he first casts it you win because guess what shunpo goes through it and it will allow you to jump him easy also he is really squishy early watch out for the stun and his ulti later on in the game but to start out with you should dominate
Janna- Has a good harass with her tornado but if you keep moving around it will make dodging them easy her shield is a pain but you can get past that by waiting for her to use it, let it wear off then jump in and hope she doesn't ulti you.
Teemo- Pain in the butt, but he has no disable so you can normally get a kill at level 6 just keep harassing him and at level 6 let the bodies hit the floor
Cassiopeia- Super mana dependent so let her try to hit you with her skills as long as you are in near constant movement you wont take enough damage to force you back and make sure you don't run straight back when you shunpo vary it a little
Ezreal- Like I said before mana dependent and skill shot dependent move around and he won't be able to touch you
MF- Has a solid slow and double shot is annoying but she starts like ashe, weak, if you harass her enough early you wont have to worry to much about retaliation
Here are some harder champs to lane against
Anivia her ranged harass/stun and her massive damage makes her hard to deal with but if you keep moving you should be able to dodge most of it and she is so slow and so weak make sure you don't dive when she has her egg and keep poking her she will fall easy enough
Annie just keep an eye on her spell count and you win
Caitlyn her range is ******ed to deal with not much to tell you but stay further back than you normally would
Ryze you have to be in his face to harass and ryze does the most damage at that kind of range so just harass with your blades until you can drop him with the full combo
Tristana her explosive shot is just annoying but she is weak early which means your harass should win out
Fiddlesticks his heal will make it hard for you to keep him low and you his fear ruins your ulti
Himerdinger do i really need to explain this
Kat a match up like this comes down to skill and level get a gank early and you should win this fight
Vladimir he doesn't have the cool downs to out heal your damage early so put the pressure on and keep it on and if he starts to get out of hand with his heals you have healing reduction built in, use it.
Kog'maw his range is hard to deal with but he is weak and mana dependent early you should out harass him
Malzahar again with the silence he is just hard to deal with in lane
Sivir good damage keep moving and she won't give you trouble
Twitch watch him when he goes stealth if you are level 6 you can find him with your ulti use that to your advantage
Here are some that will give you trouble
Zilean time bomb is a good harass and will keep you at your tower so if you see him get someone needs to gank early or you need to switch out of mid one of the only people who can really kick you out of mid
Karthus again he can spam harass and is dangerous even after dead you need to make sure you keep moving if you are up against him
Kassadin his silence out ranges you so you wont be able to retaliate as easily
Kennen has good damage good range good burst a stun
I know that I forgot a few champs I did this on purpose because I haven't played enough or any of them in mid so didn't want to mislead anyone if they see them take mid.
The biggest killer to every build is not having enough gold for the items in it that is why it is important that during the first part of the game you concentrate on two things above all else, creep kills and champ kills.
The best way to get creep kills is to move around until their life is exactly one hit for you and then you get your kill if your not the patient type don't be afraid to use your abilities to last hit, they have no cost and low cool down why wouldn't you. This seems really basic but you would be surprised at how many people aren't good at this part of the game.
The second most important part of your early game is harass/lane control/early kills. I put the three together like this because they really do go hand in hand if you harass well you should be able to out level your opponent easily giving you lane control allowing you to more easily get early kills. How you harass with Kat is I would think obvious throw a blade at them and shunpo in hit the once and run back so you can continue farming. Most people don't react fast enough or are too scared of you to retaliate. One thing you need to make sure you don't do is telegraph your harass, it makes it too easy to avoid, so the best way I've found to avoid doing this is to mix it up. When you run to harass them every once in a while just hit the caster minions they will start to second guess your intentions making it easier to harass or potentially kill them. As for the early kills you should be able to take out your opponent at level 6 if you don't kill them you will send them back in which case gank. I can not stress this enough, Kat is not very good at tower take downs so if you find yourself alone in a lane gank the side lanes it will help your team get side lane control and allow you to get some much needed gold. The best way to choose which lane to gank is first see who is low on the other team or see who has overextended.
Items are dependent on the team you are playing against don't follow my item list religiously it won't always work one thing that I can say for it is the first 3 big buys are necessary I never stray from them and they have never failed me before that being said you need to make sure you look at not only what your team has but also what the other team is doing if you see them stacking a ton of MR against you then get abyssal scepter it gives you some nice AP and good sudo-magic pen. Also if you are having a hard time with a team because of cc you can never go wrong with a banshee's veil. Don't be afraid to deviate from this build items are not only dependent on what you see around you but also on your own play style. That is to say I gave you the foundation you figure the rest of it out.
I normally don't need to go back until I have enough for the boots and mejai's but if you need to go back before that get a amplifying tome and normal boots and a couple health pots, this should allow you to lane a little longer and get the gold that you need to get the bigger items. Also if you need to go back before you can get mejai's but you have enough for upgraded boots grab a Elixir of Brilliance and go back to lane with upgraded boots and an amplifying tome if you can manage it. Rushing Rylai's is important so after you get your mejai go giant's belt this is important, very important, because by the time you get the gold for it you should be getting targeted by ganks and the extra health will save your life more often than not. After Rylai's get your Needlessly large rod and start in on Rabadon's Deathcap.
This is where I think Kat really shines, if played well she can melt an entire team down tanks and all. One thing that you need to look out for is CC so never go in on a team first...EVER, wait for your tank or a dps to soak up the CC and then go in it is well worth the wait to get off all of the blades in your ulti then to get the first kill in a team fight. One thing that I see a lot of teams do wrong is targeting, and this goes for every team with or without Kat, but if you have Kat make sure that when she jumps in on the enemy that she jumps on the furthest back and most dangerous champs. Teemos, Ashes, Fiddles, and Miss Fortunes (just some examples of high damage output champs) will all be in the back and if left alone will kill you so all you need to do is make sure you kill them first so when you jump in make sure it is on their most dangerous champ (excluding Trynd he is a much different story) so you can make sure that they die quick and without doing to much to you. The main reason that Kat shines in team fights is her passive, "After a kill or an assist, Katarina gains 25 gold and her cooldowns are reduced by 15 seconds." This means that if you get a kill or assist you get your q w and e back and 1/3 of your ulti allowing you to get some nice multi-kills.
This is important to do it will allow you to help your team more and save your stacks. Use her shunpo as a flash it is so helpful. If you are being chased and run into a bush pop ghost and shunpo your chaser right before they get into the brush this should give you enough time and speed to get away from them. Also remember shunpo targets everything neutrals, creeps friendly or otherwise, champs friendly or othewise, and wards use this to your advantage and you will stay alive provided you don't get cc'd to death. Cc is dangerous to every champ kat is no different be careful around a rammus amumu and other such champs. Keep behind your team like i said you will get targeted so it is important that you stay behind your tank let them eat the cc for you then jump in and kill everything. I know I said this twice but it is important so pay attention
Keep all this in mind, play smart, and don't get frustrated really the only advice i can give you. I am a good kat and i have been shut down early and still come back to win the game so stick with my build it will allow you to carry a team. If you are getting targeted take it as a compliment, they know Kat is dangerous and they are afraid also if you are getting targeted play more passive don't run in to a fight with out your whole team and never go in first in a team fight.
And one more thing to remember is I have lost games with Kat, been shut down and unable to build what i want, it happens don't worry about one or two stray games where your score isn't appealing everyone, even pros, have bad games just stand up dust yourself off and try again.
good luck hope this helped
Final notes and community scores
Hey guys if you have a good game with kat put your score in the comment section and i'll put the top ten in this section of my Guide. Oh and sorry i had to make it comment to vote i don't like not getting reasons for down votes and i enjoy getting feedback for up votes
also if you have any advice for formating changes on this build i would appreciate the input thanks guys
Teh Inspector: 19-6-20
Slipin Chokes: 18-8-14