Hello. That Goof here. I rather not mention my summoner name during the time being but I'm on the North American server. As you may have guessed, I am a Katarina main as well as a Zed main. This is my first guide on this website, so I know that it isn't the best and I might need to improve upon my mistakes throughout it. Feel free to point out some mistakes you find in my guide. And no, I have not received any help from anyone whatsoever on this guide (excluding a few helpful guides, you should check them out at the bottom of this guide). Anyway, my guide is about building Katarina as an AD/hybrid, kind of like Jax but not exactly since he's a bruiser (built with damage and some tankiness) while Kat is an assassin (built with damage for burst). So without further ado, let's get into the guide.

You might ask, "Why would anyone build Katarina mostly AD?" It's because of her high AD scalings on almost all of her abilities, excluding her initial Q. Let's take a look at her scalings;

Voracity
Voracity
INNATE: Whenever an enemy champion dies within 3 seconds of Katarina damaging them, her cooldowns are reduced by 15 seconds.
Sinister Steel
DAGGERS: Whenever Katarina catches a Dagger or picks it up from the ground, she uses it to slash through all nearby enemies, dealing 75 - 287 (based on level) (+ 100% bonus AD) (+ 55 / 70 / 85 / 100% AP) magic damage and reducing Shunpo's cooldown by 78 / 84 / 90 / 96%.
Daggers last 4 seconds before disappearing.

Bouncing Blade RANGE: 625 COOLDOWN: 11 / 10 / 9 / 8 / 7
Bouncing Blades
ACTIVE: Katarina throws a Dagger to the target enemy that bounces to up to 2 nearby unaffected enemies, dealing magic damage to each target.
MAGIC DAMAGE: 75 / 105 / 135 / 165 / 195 (+ 30% AP)
After bouncing to its targets, the Dagger then lands on the ground opposite from where it struck the first target. The Dagger always takes the same amount of time to land from the time it hits the first target.

Preparation COOLDOWN: 15 / 14 / 13 / 12 / 11
Preparation
ACTIVE: Katarina tosses a Dagger into the air at her current location, which lands after 1.25 seconds, and gains bonus movement speed that decays over 1.25 seconds.
BONUS MOVEMENT SPEED: 50 / 60 / 70 / 80 / 90%

Shunpo RANGE: 725 COOLDOWN: 10 / 9.5 / 9 / 8.5 / 8
Shunpo
ACTIVE: Katarina blinks to the target location around the target unit or Dagger.
If the target is an enemy, Katarina deals them magic damage. Otherwise, she deals the same magic damage to the nearest enemy in range.
MAGIC DAMAGE: 30 / 45 / 60 / 75 / 90 (+ 25% AP) (+ 50% AD)

Death Lotus RANGE: 550 COOLDOWN: 90 / 60 / 45
Death Lotus
ACTIVE: Katarina rapidly spins in place and channels for 2.5 seconds, throwing a dagger every 0.166 seconds to each nearby enemy champion, up to a maximum of 3 at a time, dealing them magic damage and applying Grievous Wounds icon Grievous Wounds for 3 seconds.
「 MAGIC DAMAGE PER DAGGER: 25 / 37.5 / 50 (+ 19% AP) (+ 22% bonus AD) 」
Death Lotus cannot be cancelled by movement and basic attack commands in the first and last 2.5 seconds of channeling.

We all know that we can get more AP for less gold and most of the abilities AD scalings are BONUS AD, but the scalings are legit enough to actually do damage. Building her mostly AD is especially powerful during her lvl 2 and 3 powerspikes, since the AP scaling on her daggers is only 50% AP while the AD scaling is a whopping 125% Bonus AD and her Shunpo's AD scaling is 65% Total AD while the AP scaling is only 25%. The sum of all her AD scalings is 147% bonus AD + 65% AD as opposed to all of her AP scalings which is 144% AP (this is all calculated at lvl 18). And in the end, we're just aiming for a fun build to play in norms just to switch things around and have some fun rather than do the same Kat build over and over again from your ranked games.

Pros:

-Auto-attacks do a lot more damage.
-Faster at destroying towers.
-Stronger early game.
-Way easier to last hit.
-Has other damage sources if enemies start stacking Magic Resist Ravenous Hydra active & Auto-attacks).
-More sustain.

Cons:

-All of her abilities deal only magic damage.
-Mainly AD build is more expensive and less cost-efficient than typical mainly AP build.
-All the Magic pen items contain no AD ( Haunting Guise, Sorcerer's Shoes & Void Staff)
-People might flame.
-AD items with Armor Pen/Lethality are not 100% effective and way less cost efficient unless you auto-attack often and/or spam Ravenous Hydra often during a fight.
-Slightly falls off earlier than the AP build due to lack of magic pen.

I'm pretty much running the generic rune page for Kat since the new runes are based off of the champion's kit's synergy with them and the player's playstyle rather than pure stats like the old ones. W.I.P.

With AD Katarina, we want to make use of AD items without armor Pen/lethality so we don't waste too much gold for an almost useless stat since Katarina deals only magic damage with all of her abilities. We also want a hint of AP to give her late game extra power and to give her initial Q a bit more damage. Items like these are a must and core on Katarina:

Hextech Gunblade: Absolute core on both AP and AD Katarina since it offers both AD and AP, heals for all damage dealt to help with Kat's lack of sustain, and a decent active that offers a slow (to make up for Kat's lack of crowd control).

Sorcerer's Shoes: Since AD Katarina will have less magic pen than AP Katarina, this is a must on her since it helps her ignore 15 magic resist from her enemies which will help her deal more damage.

Ravenous Hydra: It helps Katarina farm much more easily and do even more AOE damage during a fight with its active and passive. Since its active and passive deal physical damage, its a useful solution if the enemies start building magic resist against you.

More offensive items (optional):

Blade of the Ruined King: With some attack speed provided, it helps Katarina take down towers even faster, which can make her a good splitpusher. Its active also helps Katarina chase after a target or enter a fight quick enough (even of your shunpo does the job well enough :P)

Trinity Force: Decent item on Kat, especially with the bruiser/tank builds but I will not talk about them since this is an AD/hybrid assassin Katarina guide. Anyway, this item has good synergy with the shunpo's auto-attack reset so that Kat can deal extra damage when doing her Q, E, E, auto-attack combo on someone. It can also help Katarina take down towers faster.

Youmuu's Ghostblade: Good item for chasing during teamfights or even running away. It also offers a decent amount of AD and CDR (cooldown reduction). However, the lethality/armor pen stat is almost wasted on her which wouldn't result in a 100% cost-efficient item on Katarina. Only buy this if you like to chase, want to run away easier, spam Ravenous Hydra often during a fight, and/or auto-attack often.

Duskblade of Draktharr: It's an okay item on Kat since it gives her lots of flat AD and some extra 20 movement speed out of combat. It even gives a her the ability to clear out enemy wards every once in a while. However, the lethality/armor pen stat is almost wasted on her like mentioned above and she can't really benefit from dealing extra true damage on her next auto-attack after being unseen since she has no stealth unless she just ambushed someone from a bush. I personally don't buy this item on Katarina since most of the stats in this item are almost useless for her. Other than that, it's up to you since it's your play style and preference.

Defensive items:

Maw of Malmortius: Very good item on Katarina against a magic damage-based champion since it offers her a shield against magic damage, some life steal and spell vamp when the shield triggers, some CDR, and some temporary additional 20 AD when the shield triggers. If you feel that you're uncomfortable during the laning phase, you must rush hexdrinker and complete either Hextech Gunblade first or finish Maw of Malmortius first.

Sterak's Gage: Decent item against a dominating AD champ since it gives Katarina a shield when triggered and gives her 25% more base AD, which helps boost her shunpo damage and her auto-attack damage.

Guardian Angel: Great item on Katarina in the late game to help her be focused less and may be able to get resets from people she has killed/damaged after reviving.

Zhonya's Hourglass: This item is pretty good on Katarina, especially against an AD mid. It's also a good item to bait out essential enemy spells during a teamfight. If you are uncomfortable against certain AD champions at the start of the game, start cloth armor + 5 pots and rush armguard into Zhonya's.

Bloodthirster: Good item for Katarina due to its plentiful flat damage it gives her, a shield from the overhealing lifesteal, and enough lifesteal to help her heal to full health within a few seconds from farming minions with ONLY auto-attacks.

Situational Items:

Banshee's Veil: Get this item when the enemy team has a bunch of CC and/or getting focus a lot during a teamfight. It also offers some decent magic resist against mostly magic damage teams teams and some health to withstand some more damage. The only downside to this item is that it offers no damage since Katarina benefits from damage items greatly.

Edge of Night: An okay alternative to Banshee's Veil since it offers Katarina some damage and a shield you can activate yourself against CC and other spells. It also offers some magic resist. However, the lethality/armor pen stat is almost wasted so only buy this item when you get focused a lot and/or of the enemy team has a bunch of CC.

Mercurial Scimitar: A more cost-efficient item to Edge of Night since it offers almost the same stats as it, except Mercurial's active only applies to CC while Edge of Night's active applies to all kinds of spells. So buy this item when the enemy team has a bunch of CC.

Void Staff: Buy this item if the enemy team starts stacking magic resist. It also offers a decent amount of AP to slightly empower your late game.

This is the end of my guide. I hope you liked it and let me know how you felt about the guide, what I should improve on, what more information do you want me to put, and what is your opinion on AD Katarina. Keep in mind that this is my first guide so it won't be the best guide ever and I might need to improve on lots of things. Anyway, feel free to vote and/or post comments and I hope to see you guys later in the near future.

Special thanks to the list of resources below that helped me make this guide:

-Making a Guide

-BB Code Guide

-Katarina Abilities (League of Legends website)

-Katarina Abilities (League of Legends Wiki)