To make Katarina less delicate you need to feed her, you see the skinny girl is so frail. If you add a little bling to her attire she bulks up a lot. JK !
;p
Actually she is stupid fragile from the start to the finish of the game. She has the lowest hp of all melee champions and very low health regen. She is extremely high risk, if you land a kill you MUST move so quickly your adversaries can not target you. Your Ultimate is your highest damage ability by a ton, but it is basically a form of self crowd control and every team is going to have multiple forms of cc for you. Her early game has been nerfed massively (was already weak), you should not win lane vs anything. Farm without feeding your opponet pre 6, @ level 6 roam bottom if they are pushed. In a fair fight, Katarina almost always loses. Katarina was a weak duelist with dfg, since it was removed she simply cannot 1 v 1 without health / item / level / summoner advantages.
Katarinas E or Shunpo is her only escape and gap closer, only use this when you are committed to the play (think you can land the kill ). Basically only use this in lane to farm under turret or to escape jungle ganks by hopping to a ward. When you become more experienced you can use this to harass certain champions.
In the masterys you need to make sure you have Dangerous Game, it is really the only important mastery on Katarina. It keeps you alive when you get resets (or kill steals, because that is what she thrives on early game.). If that mastery were removed I think her winrate would drop another 1 or 2%. For Runes - Armor seals vs ad champs like zed other wise Scaling health per level seals, some type of mr glyphs, magic pen reds and either Move Speed Quints (I prefer MS) or AP Quints. There are other good options / combinations for runes but these are more than good enough to get you started.
Once team fights start, you basically afk in the back waiting for enemy cc to come out on other champions or waiting for a good chance to kill steal. Knowing when you can enter a fight and how you play team fights is the most difficult part of playing katarina. These are her strengths (and they are huge), if you do it correctly. However against many teams you simply will not have a win condition either because of the enemy teams comp or your team is weak. Generally if you think you can get half of your ultimate off on 2 or 3 people it is worth using, but when you lead with ultimate you generally will die a lot more. Zhonyas is crucial to making Kat work in team fights because it allows you to enter fights earlier than you should and enter team fights you should not enter at all. There are times when a kat initiation ult into zhonyas can be really good, I would not try it yet though. ;p
Holy crap I just typed a really crappy mini guide.
Katarina is an addiction, so fun to play. I find moving through team fights correctly and rapidly very challenging and extremely intoxicating. If you cannot do this well, you will be reported for feeding. If you go in at the wrong times, you will die and get reported for feeding. I hope you keep playing her, she is worth the effort although weak in this meta and weak over all. No champion has ever held my attention as well as this one, I do not think any other could.
EDIT: Did not realize you were not 30.
New advice:
Play her every single time you can until you hit level 30, I am not telling you to feed but to truely understand a champions limits you need to push them. Play passive until level 6 and after you hit 6 and get your ultimate, go ham. You should learn a lot while leveling.
When you hit level 30 bump this thread and tell us what problems you are having playing kat.
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