First, let's go over new features in this update!
Feature: Worn item slots
You can now slot some worn items (headwear, mask, necklace, cloak, gloves, belt, shoes) into specific slots for each character which will free up your 12 inventory slots for items you want in your backpack, as well as other miscellaneous worn items.

I've long resisted doing this because the slots are small enough that I can't display the item name over it. And when I play cRPGs myself, I often have trouble remembering what icon means what item. In Dawnsbury Days, this is further made worse by the fact that many items use stock art.
However, at higher levels, such as those that you experience in the upcoming expansion (wishlist now!), you can have enough worn items that they occupy a substantial part of your inventory and so it may be hard to keep your inventory clean and organized if you have a larger number of secondary weapons or consumables.
So, I thought this is the right time to add slots. Some items can be worn even though they don't belong to a "major" slot — you wear these items as normal merely by having them in your inventory. You can even continue wearing major items in your inventory, though whenever you complete an encounter, your worn items will be automatically slotted into the appropriate slot.
Feature: Prebuffing
You can now cast day-long spells such as Mage Armor, False Life, See Invisibility, or Mind Blank using a special long-term prebuffs system.

If you have such spells in your spell repertoire, if you prepare them or if you have them on a magical staff or a scroll, you can select them for prebuffing during precombat preparations.
You will then cast them automatically as a free action at start of combat:

This only applies to long-term buffs that last for the full day. Effects which last for only a single encounter, such as Haste and Resist Energy, are something you must still cast only after initiative is rolled (unless you're in an exploration map or otherwise are given short-term prebuff time by the specific scenario).
The main purpose of this update is for tabletop fidelity where at some point in a high-level campaign, a spellcaster may wish to simply always have see invisibility on by casting it at the start of each adventuring day.
I did receive some questions or requests for medium-term prebuffing, such as for 1-hour spells that you would cast before entering a dungeon. I've considered this but in the end so far decided that allowing for such prebuffs would not help tabletop fidelity and would instead probably result in games that would "feel" less like tabletop than now, even if technically they would be more literally faithful. This is because of how Dawnsbury Days enforces encounter order and your adventuring day, among other things. I may go over this at some point on my design podcast, available on various streaming platforms. I may also change my mind on this at some point, but not in this patch.
Feature: Area-of-effect save tooltips
When you mouse over a creature as you're targeting a cone, line, burst, or emanation effect, if that effect forces a saving throw, you will see a tooltip with that saving throw in the topleft corner, so you can assess the accuracy of an area spell before you cast it.
Previously, for area effects, you were unable to see such as a preview and so it was harder to figure out whether you should cast such an area spell.
Feature: New music
All battle music in the original campaign (Dawnsbury Days, levels 1–4) has been updated from the Lord of the Land music that was used for all the encounters into a new soundtrack, with most of the new tracks composed by Aeon Hewett.
The music for each encounter will now depend on its biome — forest, dungeon, city, or fire, for example — as well as on the type of encounter — e.g. combat or exploration.
Currently, this includes 6 new tracks. I am aware that the music volume of the new track isn't perfectly aligned to the existing tracks for now, and the new music may be a little quiteter than the previous music. You can turn the music a bit up to compensate for now. I expect to improve on the volume balance in an upcoming patch.
Staging done for the Four-Leaf Clover
All coding, writing, and art work for the upcoming expansion is now complete with this patch (except for one secret encounter). We are thus close to the beginning of the general playtest.
There is still some design work to be done, especially balancing, but that's kinda what the general playtest is for.
Right now, most of our work is spent on voice acting. This is progressing nicely. All 35 actors have been cast; we now have 24,7% of voice acting implemented in the DLC (c. 750 voice lines so far), and another 30% or so is in post-processing; and the rest is being recorded (many sessions are planned for this very week).
Please report any issues
I've gone over all error telemetry, feedback reports, and bug reports, and I believe I've fixed most issues. I'm once again sorry for the item duplication glitch last month.
This patch is a major patch that touches on core systems, however, and I'm worried it might introduce some issues.
If you notice any issue with the game, whether it's as trivial as a spell not applying a bonus from a buff you believe should have been counted, or as serious as a corrupted save file, please make a report to me, ideally including a screenshot of the problem. Please report these, even if you use mods heavily — many players use mods heavily, and so others may be facing similar problems.
I expect the release of the Four-Leaf Clover will result in more players coming back to play Dawnsbury Days and I would love to be as close to a bug-free experience as possible.
Full patch notes
This patch also adds additional character content, fixes bugs, etc. Full patch notes follow.
Features:
Worn slot items (see above).
Prebuffing (see above).
Area-of-effect tooltips (see above).
New music (see above).
Character content:
New spells: vital beacon, longstrider (I am aware there is an argument to be made that longstrider should not exist as a spell within the Second Edition framework because it's a way to increase your constant base speed at essentially no cost and with minimal requirements, and because it devalues the abilities of higher-speed characters such as monks and barbarians. If you think that the spell makes the game less interesting, I think it is reasonable for you to play the game as though the spell didn't exist. The default game balance assumes you won't always have longstrider active on all of your heroes.)
New feats: Rebounding Toss, Ricochet Stance, Spell Parry
New items: skittering mask (+ greater), master magus ring, warden's signet, accompaniment cloak, thunderblast slippers (+ greater), mirror goggles (lesser, moderate, greater), vaccine (minor, lesser, moderate, greater), sinew-shock serum, focus cathartic, blood booster (lesser, moderate, greater)
Art:
New art: greater elixir of life, major elixir of life, true elixir of life
Steam:
Achievements: Clarified in the description of "Hotel of Serenity" and "Lich" that you can find these encounters in the High-level encounters group in Free encounter mode.
Achievements: Added 56 new achievements. Most of these are tied to the Four-Leaf Clover expansion and you cannot get them yet unless you are a Four-Leaf Clover playtester. (There will be a registration form online soon where you can sign up to join the general playtest.)
Rules fidelity:
Items (reversal!): Bracers and armbands are now gloves. Headband is now headwear. (This is to reduce complexity of body slots. I recognize that his disfavors the player, and it can especially be a problem for unarmed fighters whose gloves slot is occupied by handwraps of mighty blows. We could deal with that by removing the "gloves" slot from handwraps of mighty blows, though, which might work better, and would also serve as an extra gold sink.)
Items: "Facewear" as renamed to "mask" to avoid confusion with "headwear".
Classes (Rogue): Ruffian rogue now gets medium armor expertise at level 13, and mastery at level 19.
Classes (Sorcerer): Fixed that Arcane Countermeasure didn't work against secondary arcs of Chain Lightning.
Classes (Sorcerer): Fixed that Arcane Countermeasure worked even against spellcasters you couldn't see.
Encounters (S12E4): Fixed that the cold phoenix wasn't actually weak to evil.
Items (numbing tonic): Added the Healing trait. (Technically, the numbing tonic is not a healing elixir by tabletop rules, but it feels healing-like, and so it makes sense that chirugeons should be able to produce numbing tonics more easily, which is the main effect of adding the trait. It also slightly boosts the power of the chirugeon who remains one of the weaker subclasses.)
Items (wasp guard): Fixed that it offered protection against "attacks" from allies such as the S9E5 Healing Hand ability of NPCs you free from domination.
Spells (Awaken Entropy): Now also affects flying creatures.
Spells (Blade Barrier): Now also affects flying creatures.
Spells (Cloak of Colors): Fixed that it applied on your attempts to Escape, and in some other rare situations, such as the S9E5 Healing Hand ability.
Modding:
Modding: Added CombatAction.CastsOrUses.
Modding: Added an error message if a mod attempts to add a feat too late which can trigger crashes.
Bugfixes:
Classes (Alchemist): You can now advance chirugeon past level 11.
Classes (Champion): Fixed a crash bug when a Blade Ally champion with the holy rune selected entered combat with a potion in hand.
Classes (Cleric): Fixed bug where sturdy shields weren't recognised as equipped favoured weapons by the inventory warning when selecting related feats, such as Replenishment of War.
Encounters (S9E2): Fixed that in case if you entered the hall first and kitchen second and one of your characters was standing on the exact spot where Liandra's ghost was originally found in the hall at the moment you opened a door to the kitchen, that character would cease to exist for the rest of the encounter.
Items (doubling rings): Fixed that equipping an ephemeral weapon from blazing armory or chilled armory could make it persist forever if you had doubling rings equipped.
Modding: Fixed a crash involved some modded ancestries that added spellcasting features.
Rules: Fixed a rare situation where a dead creature with swimming could spam swimming immunity errors.
Rules: Fixed that in some cases, attempting to move into the space of an unconscious large creature, such as an animal companion, would fail instead of shunting that animal companion off.
Text: Improved text of some stat blocks.
User interface: Fixed that selecting an option for some feat-like choices (e.g. for the Consistency spell or some modded selections) didn't allow the chosen selection to persist on screen in order to access tooltips and links after choosing it.
QoL:
Items (doubling rings): Greater doubling rings now always have priority over basic doubling rings.
Character content (beyond the level cap):
New feats: Preternatural Parry
New items: daredevil boots (+ greater), cloak of the bat (+ greater), jaathom's scarf, pegasus barding, clockwork shield (+ greater)
The Four-Leaf Clover:
New chapter: Chapter 6 (The Below and the Other Side). Advance to level 15, and race the most powerful demon lord to the Temple of the Coestus on the Other Side, where you must prevail in an ultimate last battle, restore the leylines of Our Point of Light and the Great Axiomatic Barrier and expel the demonic armada once and for all! This chapter concludes the Four-Leaf Clover adventure!
New encounter: Fallen from the Void (a Starfinder: Afterlight collaboration!).
Story mode: Added a world map tab to story mode where you can observe where you are in the world.
Mansion: You may now purchase additional Mansion improvements by paying gold. You pay 2000gp for the first extra improvement, then 4000gp for the second, then 6000gp for the third. You must still wait one downtime cycle before it's constructed, but this way, you may build two improvements at a time.
Balancing (S10E1): Hezrou: Kept one Divine Wrath; replaced all other instances of it with Sudden Blight.
Balancing (S11E1): Fox-Who-Sees-The-Future: Divine Wrath -> Sudden Blight.
Balancing (S12E3): Phase Drake: Chaotic Evil -> True Neutral.
Balancing (S12E3): Phase Drake: AC 33->29. Fortitude 25->21. Reflex 20->16. Will 19->12.
Balancing (S12E3): On Medium, Drake -> Weak Drake. On Hard, 2x Elite Drake -> Drake. On Insane, 2x Elite Drake -> 2x Drake.
Balancing (S13E1): On Hard, removed one bone devil. On Medium and Hard, Sadistic Erinys -> Weak Sadistic Erinys. On Insane, Elite Sadistic Erinys -> Sadistic Erinys.
Balancing (S13E2b): On Hard, only Seraphiel now has attack of opportunity. On Insane, no angel has attack of opportunity.
Balancing (S14E3): On Hard, Dinosaur Wizard -> Elite Dinosaur Wizard. On Insane, bumped level of both troops by +1.
Encounters (DM2 Mining Diamond): Fixed maximum diamond amount.
Encounters (L4 Heartbond): Fixed the ceremony seating assignment so that Linden no longer bumps into Lori.
Encounters (M5 Raising a Child): Fixed victory message.
Encounters (S10E4a, S10E4c): Fixed that the Arborea quest sequence didn't play at the end of these encounters, and that the "Arborea's friend" achievement didn't trigger if you completed one of these two encounters last.
Encounters (S10E5): Fixed that you needed to fight the Soul Eaters on harder difficulties even if you answered the door riddle correctly.
Encounters (S11E1): Fixed that the game could crash sometimes as Izzy attempted to transform.
Encounters (S12E3): The corpses of Mag'norn and two hamatulas are now visible on the map.
Encounters (S15E1): Extent of movement line now better visible.
Mansion: Fixed that if you restarted a side-encounter or a slice-of-life cutscene and then finished it successfully, you would skip the next mainline encounter.
Monsters (Carnivorous Crystal): Now immune to bleed, and splits on any physical damage, not just bludgeoning, but only if the damage gets through its damage resistance.
Monsters (Nalfeshnee): Light of Avarice now makes it clearer what item is being targeted.
Monsters (Nalfeshnee): Light of Avarice now targets a maximum of 4 items.
Story mode: Fixed that resources expended on expeditions did not refresh after your return from an expedition.
The Four-Leaf Clover voice acting:
Voice acting progress: 24,7% (738/3113 lines).
New voice acting: Lenka, Keia, Narrator, The Inevitable, Fox Who-Sees-The-Future, Lori, Twin Heart.
New voice acting: Annacoesta (chapter 1, except S10E3, chapter 2).
New voice acting: Saffi (chapters 1 and 2).
New voice acting: Tok'dar (chapters 1–5, side content).