Ok, we've gone through the three classes in Playtest 8, but here we're going to touch on what are really the truly big changes, and I think these will be a bit surprising.
The spells being tested mostly fall into two categories: "Conjure" spells and healing spells.
Healing spells are a little simpler: they've generally been buffed. Anyone who has played a Cleric or other healing class will know that these spells can sometimes feel really pointless - you cast Cure Wounds on an ally and heal them for 7 HP, only for them to get hit for 14 HP the next turn. Indeed, I think a lot of damage mitigation features and abilities tend to be more valuable in-combat that actual healing in a lot of cases, but the buffs here are meant to make healing in the fray a little more attractive.
Cure Wounds:
This spell has just gotten a huge buff: the base, 1st level version now restores 2d8 plus your spellcasting ability modifier, rather than 1d8, and each level above 1st adds an additional 2d8. While this doesn't technically double the spell's healing, it comes close, especially as it is upcast. A 3rd level Cure Wounds cast when you have a +4 to your spellcasitng ability will do an average of 31 points of healing, compared to its current 17.5.
I actually think buffing healing spells could, in a roundabout way, actually empower non-spellcasters further. If health is regained at a higher rate (and at a cost of spell slots,) the sustainability of classes that don't rely on spell slots will effectively be more attractive.
Healing Word:
Like Cure Wounds, the dice here have doubled, with the base 1st level version granting 2d4 + spellcasting ability modifier, and each upcast level adding 2d4.
Mass Cure Wounds:
The base healing of this has been increased to 5d8 plus your spellcasting ability modifier.
Notably the scaling of this spell has not gone up, only gaining 1d8 per spell level (though you could argue the total healing is up to 6d8 per spell level, given that you're healing so many targets). Still, overall a buff, even if only by 2d8 (or 12d8 using that logic).
Mass Healing Word:
Mass Healing Word now has a base of 2d4 plus spellcasting ability modifier, meaning that at 3rd level it is truly like casting a Healing Word on up to 6 creatures. Like Mass Cure Wounds its scaling is just a single die per spell level.
Power Word Fortify:
This is brand-new 7th level spell with a 60 foot range available to Bards and Clerics. The spell provides up to 120 temporary hit points, divided evenly between up to 6 targets. So, you could either put a massive amount of Temp HP on a single target, or potentially get 20 for each of a party of 6.
Notably you have to divide this evenly, so if you have a big disparity in how likely members of your party are to take damage, you might consider leaving out the more elusive members to boost the Temp HP of the party members who tend to get hit a lot. 120 Temp HP is nothing to sneeze at, though of course it won't stack with other sources.
I think the really important changes here are to the two 1st level spells. Cure Wounds in particular I think is often not worth the action to cast it because the healing potential is usually not as useful as the damage you could potentially deal to a foe with that action. This is a buff to be sure, and makes it perhaps more viable, if not perfectly so, to spend that action and spell slot on the heal.
Now, let's look at the Conjure Spells.
Notably, the 2024 PHB is going to be adding the "Summon" spells from Tasha's Cauldron of Everything. These spells are very popular and straightforward, and will be largely taking the place of spells that "put more bodies on the battlefield."
So, what of the "Conjure" spells from the PHB?
They're here, but they're all radically different, and conjure persistent spell effects that take the form of conjured spirits. Let's go down the line.
Conjure Animals:
You create a Large swarm of spectral animals in an unoccupied space you can see within range (60 feet). The swarm lasts for the duration (10 minutes with concentration). When a creature hostile to you enters a space within 10 feet of the swarm for the first time on their turn or starts its turn there, you can make a melee spell attack against the creature. On a hit, the target takes radiant damage equal to 2d10 plus your spellcasting ability modifier.
You have advantage on Strength saving throws while within 10 feet of the swarm, and when you move on your turn, you can move the swarm up to 30 feet to an unoccupied space you can see.
When upcast, you add 1d10 to the damage for each slot above 3rd.
So, one thing I'm a little unclear of is whether the swarm occupies its space, or if you can pass through it. Still, it's a magical object with no HP, so the only way to get rid of it is to dispel it or knock out your concentration. Notably its damage does not require any action on your part.
Conjure Celestial:
You summon a protective presence of a Celestial spirit, which manifests as a pillar of divine light that shines in a 10-foot-radius, 40-foot-high cylinder centered on a point within range. Bright Light fills the cylinder, and when you move on your turn, you can move it 30 feet.
When a creature enters the Cylinder for the first time on a turn or starts its turn there, you can cause one of two effects: If they aren't undead or a construct, they can regain HP equal to 4d12 plus your spellcasting modifier - though this can only happen once per creature per casting of the spell. Alternatively, the creature must make a Dex save or take 8d12 Radiant damage on a failure or half as much on a success.
This one is a little less ambiguous, with potential for a lot of damage (and you can always just move the conjured spirit over a target) and some decent healing, and perhaps most importantly, it does both.
Conjure Elemental:
This creates a 10-foot cube composed of air, fire, earth, or water (you choose when you cast it). If a creature that is hostile to you moves within 5 feet of the spirit, you can make a melee spell attack against it, dealing 8d8 damage on a hit - bludgeoning for Earth, cold for Water, fire for Fire, and lightning for Air. If the target is Large or smaller, it also gets pulled into the cube and is restrained. While restrained, at the start of its turn, the creature must make a Strength save, taking 4d8 of the same damage type on a failure or freeing itself on a success. The spirit can only restrain one target at a time.
Here's an oddity: if the creature succeeds on a saving throw to escape the restraint, they'll presumably need to Move to leave the area of the spell. And then, because they Move within 5 feet of the spirit (inside it is within 5 feet) the spirit should get another attack on the target, and if it hits, the target is restrained again. So, this might be overpowered, as it could pretty easily lock down a foe, even if they succeed on their saving throws.
Conjure Fey:
You summon the awesome presence of a Medium Fey spirit in an unoccupied space within range. When the spirit appears, you can make one melee spell attack against a creature within 5 feet of the spirit, dealing 3d12 plus your spell modifier of psychic damage on a hit. If hit, the target must make a Wisdom save or be frightened until the start of your next turn. As a bonus action, you can teleport the spirit up to 30 feet and repeat the attack against a creature within 5 feet.
So, is this better than Summon Fey? At 6th level (which is the level of this spell) Summon Fey does 1d6+9+1d6 (mostly piercing damage) three times, or 48 average damage on all hits. This deals likely 24.5 damage. However, this spirit cannot be attacked or otherwise destroyed. It's a trade-off, which is probably for the best.
Conjure Minor Elementals:
You summon elemental spirits that flit around you for the duration. Until the spell ends, any attack you make deals an extra 2d8 damage when you hit a creature within 15 feet of you (you choose between bludgeoning, cold, fire, or lightning damage each time you deal this extra damage). Additionally, the ground around you for 15 feet is difficult terrain for your enemies.
When upcast, the damage goes up by 2d8 per level beyond 4 and the radius of the difficult terrain extends by 5 feet per slot above 4.
So, this is going to be less appealing to ranged spellcasters, but I think we should also point out that, as a Wizard spell, Eldritch Knights who have 4th level spells (so tier 4) will be able to use this. I do think this will be more appealing for a Moon Druid than most Wizards, especially if they use a form that has several different attacks (between Primal Strikes, Lunar Strikes, and this, you might be rolling a whole lot of dice every time you hit).
Conjure Woodland Beings:
If memory serves, this is the one that was absurdly overpowered as you could conjure like 8 Pixies that could then all cast Polymorph to turn the party into a bunch of T-Rexes.
The new version is actually similar to Spirit Guardians. For the duration, spirits flit about you within a 10-foot radius, and when they enter that space or start their turn there, they make a Wisdom saving throw or take 5d8 Force damage or half as much on a success (the same damage as a 5th level Spirit Guardians, though with the ever-reliable Force). Additionally, while this is up, you can Disengage as a bonus action.
While it doesn't have the absurdly powerful interaction the old one had, Spirit Guardians is a popular spell, and this is pretty similar in terms of power - and the Disengage functionality gives you the chance to run it through a crowd of foes.
So, overall these Conjure Spells are definitely not going to be anything like the older versions of them, but each of them seems to have its use and appeal. More importantly, they aren't going to be an utter pain in the ass at the table, and I'm very much in favor of that.
Finally, we have a couple of miscellaneous spells:
Fount of Moonlight:
This is a new 4th level spell for Bards and Druids. It has a range of self and lasts 10 minutes with concentration.
Light wreathes your body, emitting bright light out to 20 feet and dim light a further 20. Until the spell ends, you have resistance to Radiant damage and your melee attacks deal an extra 2d6 Radiant damage on a hit.
Additionally, immediately after you take damage from a creature you can see within 60 feet of you, you can use a reaction to force the target to make a Con save, and on a failure the creatuer is blinded until the end of your next turn.
This is one of the Circle Spells for Circle of the Moon, and really shows how the Moon Druid can stack up a lot of extra damage on its attacks, once again really showing there had better be some good Beasts with multiattack. This could also be pretty good on a Valor Bard. This does take an action to cast, though, so you'll want to pre-cast the spell before combat if you can, as it might take a few turns for it to make up for a lost action on the first round of combat.
Starry Wisp:
This is a brand-new cantrip for Bards and Druids. It has a 60-foot range. You launch a mote of light at a creature or object in range, and make a ranged spell attack. On a hit, the target takes 1d8 radiant damage and until the end of your next turn, it emits dim light in a 10-foot radius and can't benefit from going invisible. As with most damage cantrips, this gains a damage die at each new tier of play.
This is fine - a decent, not terribly flashy (well, I guess literally flashy) damage cantrip that should fit very well with a Circle of Stars Druid (and can be cast by Moon Druids in Wild Shape). Given that Druids and Bards have both had pretty underwhelming ranged cantrip options, this is very welcome. Notably, like Fire Bolt, this can target objects, which you might be surprised to realize is not powerful with most damage cantrips.
And there we have it: with the three classes and these spells, that's the meat of Playtest 8.
My overall impressions are positive. I'm not entirely sure if the Monk changes are enough, but I also realize that I've been down on the Monk so long that it might be that nothing short of actually seeing one do well in play will be enough to be convinced it's fixed. But I like Brutal Strikes for Barbarians, and I think that other stuff in the test is mostly pretty good.
This might be the last playtest we get focused on classes. I believe there were 10 playtests planned (not counting the Bastions and Cantrips one,) meaning we're really getting down to the endgame on this UA process. With the books coming out next year, I imagine they'll need to wrap up this process pretty soon if we're going to get the new books in the latter half of next year.