love u

Lich Bane :) I always like replacing Lich Bane with another item if I need it. However, you can replace it with Rabadon's too if you want.

You're welcome man! Thank you for reading it as well. If you have any questions, feel free to ask here :)

Yeah Tank Top is OP but unless you're dedicating yourself to building entirely tank items, you should get BoTRK first since if you rush Titanic Hydra (or some other item) you are not going to be able to 1 v 1 an actual top laner. (was 3/0, built Titanic and that 3/0 lead turned to 4/7 as Aatrox kept on towerdiving me, and I couldn't kill him) You can not go BotRK if you want, but it does make you pretty useless in 1 v 1ing the other top laner.

It's always bad to get Night Harvester second, or even worse, first due to how weak it is compared to other items like Lich Bane/Void Staff/Demonic Embrace. There is no reason why you should want a 40 second passive rather than something that works every 2.5 seconds on Kat, since Kat's entire kit now is basically on-hit. It's way better to rush a Lich Bane or other items. Katarina doesn't need a mythic item until later on in the game. All her core items are legendary.

Building BotRK in every build is insanely good. Without BotRK, you will basically become "active" at around 3 items in. This means that before that, you feel very weak without it. Nashor's Tooth is however a good substitute but it doesn't remove the glaring problems that not building AD on Kat early has. Katarina scales insanely well off AD early. That is why when Gunblade was there, we always built 2 long swords before transitioning to Revolver, Bilgewater Cutlass and then Gunblade. After that, some users like going Death's Dance since she still sclaed very well with AP.

On builds like Night Harvester that is even more important, it is important that you get BotRK early since you basically have no Keystone. This means that you'll be very weak and you'll use the help you can get from BotRK's AD, sustain (15% lifesteal), attack speed (more auto procs and ultimate damage since it scales), and the 10% physical on-hit it does with every attack, as well as the 3 stacks slow + more damage.

Hi!
No, Conqueror is 100% better than Fleet Footwork in all stages of the game. For me, Conqueror is more of a damage tool rather than a sustain tool. It only really becomes really good at healing during teamfights rather than laning phase as oftentimes, enemies die before you get to 12 stacks, or they would disengage from the fight.

Especially since they "nerfed" Conqueror to have less healing and more AD, it has become even more of a powerhouse during laning phase (level 2 and 3 in particular) where your autos hit like a truck, and it can catch Yasuo players offguard as they get very cocky when seeing a Katarina challenge them to a auto-attack duel.

Although Fleet Footwork might have sustain, there is a reason why Blade of the Ruined King is built, and why Doran's Blade is recommended as such a good first item to get.

If you have any further questions, please feel free to ask. Thank you! :)

You're even hotter ;)

Hi there!
Honestly, I don't feel that Thornmail is a good item to get on Katarina, unless you're playing Bruiser Kat with Grasp, where you can get armor later on in the game. This is primarily due to 3 reasons.
First of all, Katarina already has an item she can build that'll help her out immensely with heavy-ad champions, and that is Seeker's Armguard. It gives her AP and it gives her armor.
Another reason is because Katarina doesn't benefit much from the Grievous Wounds. Since she already has Grievous Wounds on her ulti, it is a useless stat to have on her, and if she really wanted Grievous Wounds, she can just get Execs -> Mortal Reminder for a niche AD build, or Oblivion Orb -> Morellonomicon which isn't recommended now anyways.
The third reason is because if she builds normally, the thorn effect doesn't really work on her as she has no other armor items to scale off from, as usually with Thornmail (basing my knowledge from S10), you would build other armor items first and then Thornmail so that the Thorn has more damage. Dead's Man Plate seems stronger on Kat than Thornmail anyway (although it still isn't recommended)

Hope it helps! And if you have any other questions, feel free to ask me. :)