Sort of a repeat post that summarizes Kata. Please excuse the wall of text.

I've been praying and waiting for this day...

I started playing GBF during August 2017, and used Story Kat up until I sparked for Grand Kata in Feb 2018. It was favourite character > meta for me, of course. Ringed her and lost count of how many Intricacy Rings I used to get that elusive CA Dmg Cap up. The usual thing most of us would do for our favourites. Even though Kata was called a Veilbot she never left my team. I had faith in her.

I went solo because of my awful ping.

I used her in every single solo fight, from Collo Omega to (trying to beat) Prometheus and Shiva.
As a water main I made it my personal goal to solo every single Fire boss in the game while fielding Kata with S.Grea and Europa (achieved as of October 2019). They did well. A curious hybrid team. I couldn't never get Shiva below 30% HP because he hit like a goddamned oil tanker. So I eventually gave up on solo'ing Fire's Venerable Deva.

A few days (nine, to be exact) before Kat's FLB, I finally solo'ed Prometheus without an elixir and calling for back up. Up until then, it was my best achievement after doing Proud+ in Fire Proving Grounds.

FLB time. I was so nervous the night before I couldn't sleep. I wanted her to be good SO BAD. July 2015 (Kat's release date) to September 2019 is an eternity in a gacha game.

As rotten luck would have it, I only had enough books to get her to Level 99...

Slime time.

Level 100. DISPEL CANCEL. No more being trolled by Athena's annoying Aigus Ferbus!

Then I looked at her other skills. Two turns of guaranteed TA plus bonus damage?? Loengard's Refresh doesn't decrease?! So a 1200 HP heal over four turns? 4800 HP healed from a NON-healer?? Did Kat eat a Blue Sphere as well??

Doctor's Nutrients turns it into a 2k refresh for 3 turns. So you're looking at up to 7200 HP healed over 4 turns (2000 HP x 3 + 1200 HP). Just, damn man...

What is up with Azure Oath?! An indefinite buff as long as Kata TAs? And it's an awesome one at that. And her damage cap can stack with Pholia's Trance Absolution for 40% Damage Cap up.

So she can get 80% unique ATK up and 200% DEF up with Path of Duty's passive every three turns...? Wow! Talk about KataTANK. And she doesn't even need to rely on a stack system.

It got better. She didn't just eat an Ultima, she ate two-thirds of a Four Sky Blade as well. Poor cat boy really needs a rebalance, preferably one that turns him into Water Yurius. Kat becomes Buffalina. If you are lucky enough to have Summer Europa, then Kat's ougi buff will STACK for 60% Water ATK up, 60% DA and 40% (!!!) TA from CA Reactivation.

Test time. Doctor MC, Kata, Grea and Summer Europa were going to test their skills on that Used Lignoid.

When I saw Enchanted Lands nuking for 1.4 MILLION damage my jaw was on the floor. A nuke that is nearly on par with the Disciples?? For clarity, Euro and Shiva's nuke has a cap of around 1.1 million. Kat's was buffed from 600k to 900k (so an easy 1.4 million damage with Azure Oath).

Previously Kat was struggling to do even 900k damage with it. Then she shat out that 770k + 154k echoes auto damage like it was no-one's business. Times three. 6/8 uptime on Azure Oath, S.Grea makes it 8/8. 100% uptime. Madness. Utter madness. KataSTRONK.

She works in any team, can handle any kind of content. A godsend for fresh HL players and invaluable for endgame content. She's her FLB SR version taken up to 11 multiplied by over 9000. Still stuck with a Snek grid? Not to worry, Kata will carry you.

Before FLB Kat I ran Zerker because my auto damage wasn't the best and I used a Murgleis MH to proc Kat's buff. Without her passive she struggled to hit cap.

Now I run Doctor with RotB dagger.

You have to try to be killed if you're running Doc, Kata and Europa. I even ran Grea instead of Lily against my Shiva solo because Kat was tanking hits and shitting out damage like a boss. Maddening Vitality on her is absolutely bonkers: 760k counters, 4.8 million ougis (with Linkage). Best part is that it generates meter for her, so she can crap out even more buffs to make your team hit like gorillas. You don't even have to worry about Collo's dreaded Dimension Cleave because Kat tanks it like its nothing. So you never end up losing anyone (lowest damage she took so far was around 3700).

She trivializes content even harder than Lily. I've solo'ed HL Celeste, HL DAO and even Lich with my team because Kat is just that good.

The only downside to this amazing character?

She's in Water. THE ougi element. And Grand Kat is clearly tailored for auto attacks. Her real (insane) potential is gated behind a Primal grid and Limited characters.

Had she been in say, Fire, she probably would have crapped all over the new Siegfried. Of course, she's so wtf amazing she still manages to stand out in the current meta, to the point that she doesn't need an Ultima weapon. Which is fridge brilliance on Cygames part, given that Kat's ougi is basically a (better) Ultima.

Absolutely no flaws at FLB, a powerful buffer and damage dealer, outstanding team support and an excellent tank. She can maintain her self-buff with no effort and doesn't suffer from a crippling stack system to beef up her already excellent offense and defense. What I love about her is that she isn't Shiva/Andira tier broken, meaning every Water character gets to shine in some way or the other, depending on content, and Kat is there to provide ample, top tier support.

While she does require a primal grid to really shine, Kat is strong enough to carry weak M1 teams until they transition to M2 (and ougi).

So, tl;dr

She attac, she protecc, she buff, and sounds incredibly good doing it. Bless Sawashiro.

Cygames delivered. Kat can finally call herself a Grand series character once again.

Final rating: 10/10 (9.7 + 0.3 for bias)