I am actually liking the mechanics in actual gameplay. The autodamage is low but effective.

1 hit point zombies drop pretty fast. Much less of a headache than conjuring 8, 16, 24, or 32 beasts with a conjure animal spell. As long as the player is focused on playing it can go pretty fast. I wouldn’t recommend these types of actions for every player. I spend less than 20 seconds for my turn and am using 3 attacks. Some players can spend 3 minutes for a single attack. Some times I wish each player would only have 1 minute to accomplish anything they want and if the player didn’t finish their turn in that time, they have to wait for the next turn to go.

I experimented a bit with an EK and thought it had its moments. I’m not sure the class itself is bad, but it’s rather constricted. It’s not unusual for a lot of the first classes in an edition to need some revision or opening up and I think a number of the PHB classes illustrate this. Of course, WotC seems to be incredibly reluctant to do that.

Addendum of things I realised after ranting to a friend:
When you gain spreading spores your halo of spores base damage is 9. That is enough to instantly kill any commoner. There are also no limits on the number of zombies the spore druid can have.
The spore druid throws out the spore cloud, walks through town, slaughters the commoners, now has 30+ zombies under their command for an hour. I don’t need to say how horrible this is for simply running fights.

This UA makes me nervous because it’s just so bad. The fact someone at WotC thought this was acceptable at any point means that someone thinks this is okay. Hopefully these classes get dropped like so many bad UAs have but these classes are just *so* egregious.

Someone at WotC thought immunity to 3 common conditions, a damage type and *critical hits* was okay.

Brute is in every way a step backwards for D&D and the fact that this was made – even for a UA – makes me a little nervous. It is basically a champion fight with better damage and exists for the sake of existing. It’s nothing but power creep.

I actually don’t like the school of invention. The flavour is a bit generic, it’s just “oooh, mad wizzzard”. Arcanomechanical Armor is a dull feature. It gives you resistance to the second rarest damage type in the game, locks you into a specific armour type and doesn’t really carry much in the way of feel or interest for me. Why can’t I have regular leather Arcanomechanical armour? It doesn’t actually provide any bonus AC compared to regular studded armour so why can’t I use it on medium or even heavy armour if I somehow have proficiency in them – a Dwarf Invention Wizard in half plate armour sounds great.
I can’t think of a single instance where reckless casting is a viable alternative besides “everything’s gone horribly wrong, let’s go for a hail mary shot.” If I’m neck deep in trouble and reckless cast a 2nd level spell, I could want a damage spell like Scorching Ray or Shatter and get blur. For every time you roll a 10 and get to cast two great spell, you could just as likely get two spells that are irrelevant to the situation. False life and Jump are just as likely as Chromatic orb and Magic missile. In fact, some of the spells on the tables like darkness, gust of wind and the AoE damage spells centered on self can be detrimental to the party and there’s nothing in the wording of Reckless casting that says you can back out if you get spells that will endanger you and the party – in fact the name suggests that’s supposed to be a distinct possibility.
Alchemical casting to me just seems like a much weaker version of the Lore Wizard’s core feature (which isn’t strictly bad on it’s own). Swapping between the five main damage types is situational and there’s a handful of monsters that resist all five of those types. Getting 2d10 force damage out of a 2nd level spell is good but it also strikes me as something that’s either weak or great.
Prodigious inspiration isn’t as good as it sounds, feels more like a ribbon ability to me, because wizards can prepare quite a lot of spells anyway and in the games I’ve run myself I’ve never seen a situation where a wizard NEEDED a spell he didn’t have.
Controlled Chaos is a great capstone, and would be potentially overpowered if it wasn’t for how likely it is for reckless casting to give you something useless for the situation you’re in.

The school of invention as it stands leaves a lot to be desired for me. I’d like the reckless casting tables to be a little bit more evened out. I get it’s supposed to be random, but the spells are often fundamentally different. There’s a world of difference between levitate, darkness and scorching ray.

I doubt it. Considering how long they had to preview content in UA, including some subclasses coming out well over a year earlier, I’d say they declared a content freeze for XGTE a few months back, and this is the first of their new creations after that content freeze. I think we’re starting the long-long road to a putative XGTE 2.

3) Agree! Reading that trilogy now. Just started book three.

I commented below that the School of Invention might be the best Artificer class we have seen in 5e.