The out of battle hotbar and the rightmost UI menu remain present in-battle. In addition to that, the battle menu stays on-screen when selecting actions. This happens specifically to GM slot characters.
(Thank you Zerg for the information and GIF.)

In a battle i Had today, I used swap position on one of the create shade shades in Korvara. I swapped onto their tile, and the shade was still there. On me. And the player was now invisibly in my old location. He was there, but invisible.

The new round started, he took his turn, everything seemed fine. . . Until he used create shade again.
I hit him with lords flame twice, and the shade didn't break. I was hitting the correct one, but the player didn't show up, I still couldn't examine him, and he was still a shade.

His next turn, it showed he was in fact on that tile and taking damage from the attacks.

Additionally: You can space swap on your own tile. So you just . . . Swap in place. This feels unintended, and also has the poor effect of ALWAYS defaulting to that. So if you're used to the skill auto targeting the nearest enemy, like I am, you might just instantly hit Z after using swap position, and just. . . Waste your momentum by swapping in place.

It seems that Youkai Evoke spells don't receive any boost from power from effects that boost the power of spells.
They're still considered spells, and they're still able to be stopped with silence, so this does seem like a bug, as nothing says that this should be the case anywhere in the game.

I've tested with cast order, and with pure power, and with evocation. (The Evoker passive)

This also applies to Needle, (Equipping and unequipping pure power while having nothing equipped didn't change the initial damage of the spell at all, nor the final damage against the prinny)
These are so far the only spells to have this issue that I've noticed. Even runes get the damage boost.

If I had to guess, its that it isnt applying to spells that don't take SWA into consideration? 
Needle even uses a casting implement, so it can't just be spells that don't use weapons.

Also the evocation passive of evoker doesn't seem to trigger at all, while you have no torso equipped, despite it supposedly supposed to count as going unarmored. It does specifically say 'unarmored torso item' but I think that's just what it normally is supposed to say?

A few bugs I've noticed with the Phase Python Youkai:

1: When Phase Python is defeated, the poison he's inflicted stops doing damage. The opponent will remain poisoned, it'll tick down every turn, but absolutely no damage is dealt.

2: Phase Python's hit rate seems to be. . .Showing incorrectly. I'm not sure if its not taking flanking into account or what. But his evoke skill shows a lower hit rate than his basic attack, and he managed a clean hit on a character that showed a -11% chance to hit against, with the evoke skill.

Steps to replicate: Summon a phase python.
Use the evoke skill.
Poison someone.
Get killed.
New round won't do poison damage.

A new Donation item the Asago Radio! It has only one purpose to play in-game tracks that only you can hear rather it be Sigrogana music or Korvara music.

Evasion builds are already incredibly feast or famine while requiring major stat investment. You ideally want to hit and maintain the upper cap of 50 in buffs, with extremely dedicated evade builds often maxing out at around a little under or over 200 depending on race. This ends up being an issue in that very few classes actually give consistent enough evade buffs to hit the 50, which seriously restricts builds (you're basically forced into using a rogue class for most builds if you ever want to hit it for more than 1 or 2 attacks since they're versatile enough to pair with most other classes.)

With changes to things like Windswept Gi being reduced to 15 evade for 1 hit only and many other evade buffs only lasting for X (usually 1) amount of hits (miragewalk, dancer dodge, disengage, etc.) this becomes a serious issue in any sort of teamfight where multiple instances of damage are being hurled your way on top of evasion ignoring skills.

Could things like windswept/mirage walk/dancer's agility be perhaps changed to have their evade instances stack (if you use a wind spell twice, you get 2 dodge buff charges) instead of one? Increasing them to give two dodge charges instead of one would be welcome but that might be too strong in certain situations. Another alternative is to give them lower initial buffs but make them gradually stack higher like Chaos Reflex or Verglas' Hare's Agility.

Also more consistent evasion buffs even if they have to have certain activation requirements (Firebird's Feather Veil or the aforementioned gradually stacking ones like Chaos Reflex) being available to other classes would be nice for build diversity. The windswept gi change actually butchered almost all the alternative janky mage builds I wanted to do.

I have managed to locate a tile on the goblin cave that lets you cross into the void. 

The tile in the attached image (circled in blue) can be passed if you moved it diagonally. Doing so clips the map and enters the black area. I have replicated this multiple times and can log in to show it if needed
   

Grandovyn's Potential Skill, Swordsmith Rain can roll infliction for Lingering Damage even if you miss the enemy. Part of me wonders if this is intended, though, since it is a sword rain..

The title says enough. Due to 'Two-Handed' only affecting Axe, Sword and Spear, it allows people building those stats to save points for no real drawbacks but to not have a shield or sub-weapon. +20 SWA is very stat-efficient, which leaves Bows and Fists, weapons that also scale from STR but don't have baby wheels, to open a lot of exploitable holes in your building process.

Namely because their damage vastly differ from the Sw/Ax/Sp/Tom meta. So I think there should be a change, either nerfing Two-Handed, or making something similar to it to other types, such as the more glaring ones like Fists and Bows, who often suffer from low SWA.

Fists (Double Flurry)
> Having two identical Fist weapons equipped (i.e 2x Brawler's Glove) reduces the momentum cost of Basic Attack and Martial Artist Offensive Skills by 1.

Bows (Free Handed)
> Having no sub-weapon equipped increases Critical Damage by 50% of your Strength as a flat bonus damage.

Bows (Arbalest Passive?)
> Having a sub-weapon equipped increases Critical Damage by 50% of your Strength as a flat bonus damage.

I am unsure if this is intended but it seems like when you move once for 3 Momentum it changes movement to costign 5 momentum.