About Katarina.

Katarina is a midlane assassin, with a huge carry potential. She has one of the best scaling into lategame, and is a very balanced champion in terms of mobility, farming and roaming. Since Katarina has no mana you can spam your spells whenever they are off cooldown, this does not only give you a safe lane for the most part but also allows you to farm the jungle and harrass at will without being restricted by mana.

About myself.

I am Henrickvds, and I have been playing League of Legend for about 2 years now. I am Diamond I on the EUW servers, playing mostly mid lane and ADC. I like playing roles which require a lot of micro-management (micro-management involves kiting, hitting skillshots, and comboing your abilities rapidly). Mid lane and ADC fit this description very well, and so does Katarina!

A little sidenote.

Please do take into consideration that I am very new to making guides and do not know how everything works yet. Also English is not my native language so please forgive any spelling errors. Any constructed critisism is more then welcome!

Katarina is a very versatile champion. She has a lot of pros and cons, but you can counter most of the cons by playing properly.

SPACE

Pros +One of the best scaling into lategame and carry potential +She has no mana. +A lot of fun to play! +Very good roaming. +Can farm very well (again, no mana).

SPACE

Cons -Very weak early game. -Requires a lot of practise. -Very susceptible to CC and silences. -Needs someone to engage. (More info on this is the late game&teamfights chapter) -Hard to play.

Voracity
This is what makes Katarina what she is. Everytime you kill someone, your Q, W and E will be up again and after 3 consecutive kills even your R will be up. The teamfighting capacity of this is enormous and 1 reset often causes disaster in the enemy team.

Bouncing Blades
Bouncing Blades is your main harassing ability and also the spell you will be maxing out first most of the time. When using this ability you wanna look for openings which allow you to hit your opponent and have it bounce to minions. Another thing you can do with this spell is deny recalls under turret by hitting a incoming creep wave and having it bounce on the enemy champion, this is not always possible as you need a fresh creep wave to do this

sinister steelSinister Steel
Sinister Steel allows for last hitting without having to pop your Q or coming in basic attack range of the minion, put 2 points in this to make last hitting with it easier as last hitting with a lv 1 Sinister Steel can be quite difficult. The only time you really wanna max this is when the movement speed is essential, or if you are constantly trading blows. This spell also allows you to get away from ganks or get in position for a better ult by utilising its movement speed buff. By first using this spell and then following it up with a shunpo to a minion you can make a clean getaway

Shunpo
Shunpo is your main mobility spell, its used for getting in and out of fights and dodging skillshots. You are going to max this lastly since it deals little damage and doesn't offer a lot besides mobility. Shunpo can be used on wards and other objects which are treated as a minion like Jarvan IV's Flag Toss, or Zac's blobs.

Death Lotus
Death Lotus is your ultimate abiltiy, it has a huge AP scaling and deals a ton of damage if used properly. Many people see this ability as Katarina's main damage tool and they often think if this is cancelled, Katarina is completely useless, which is far from true. Early game this ability won't do a lot of damage, and it's best to use it for trades. When you see your opponent throw his/her spells on creeps this is a good opening to use your full combo to harass and assert some pressure in lane.

The early game for Katarina isn't very active, the chance of getting a kill pre 6 is very low. Unless you are facing a nidalee without Barrier, you are likely to get outpoked and trades won't go well. What you should do is just sit back and farm up with your Bouncing Blades. Do not be afraid to lose a cs or two, this will happen. A smart way to approach the early game is to inspect the playstyle of your opponent, some play really passively allowing you to last hit with your basic attacks while others can be overly aggressive denying you pretty much all cs. Just keep a cool during this time and make sure that you get in XP range. Whenever your opponent is zoning you out of xp range and you can't take him head on, you should call for your jungler asap, however most of the time you can just push him/her back becuase if he/she pokes you Here are some basic rules to go by.

Rules of thumb

[*]Prioritize farming over harassing.
[*]Losing a couple of cs is fine, it will happen.
[*]Stay in XP range.

Alright now that you have made it through the early game Katarina's weakest point has been surpassed. You should have some magic pen built up by now and be able to shove wave with some ease. Now the question I get most often when I tell people about my succes with Katarina is: "but when do I start roaming?". This is very situational and to find out when it is a good time to roam check out this little list of requirements for a successfull roam.

When to roam

• Will you lose a lot of cs or a turret?
  if yes then this is not the time to roam
• Do they have wards?
  if they do you usually don't want to roam, however if you think it will be too late already when they see you, you can go for it.
• Is the lane which you are trying to gank pushed?
  If it isn't you generally can't get a gank off, only proceed to turret dive when you are a 100% certain of success.