The big update

Mastery is now two webs, one for skilling and one for combat. The town has the Crossing Well and Town Tasks, your gear has a window of its own, every skill has a Guild and a pet, and Exploration goes to 120. With Sightings while you gather, the Collection Log, attack types, fights that look better and new tools at every tier.

Mastery

Two webs: start at your roots and spend points along a path, taking notables on the way. Oaths are the big nodes: a big gain that comes with a cost.
Points: they come from your levels, Renown past 120, the Trials and your Guild ranks. The Combat web has points for melee, ranged, magic and a shared core, the Skilling web for Gathering and Artisan.
Your old Mastery: the Combat Mastery boards and their Oaths are replaced by the Combat web. Every point you had is yours to spend again. A fight that was running when the update came has stopped: set your web and start it again.
Free respecs: a respec is always free. Search the web, see a path before you take it, compare a suggested build with your own and keep five presets. The Skilling web can swap its preset by what you are doing.

The town

Town: the Town button in the top bar stops your work and you rest in town. It asks first only when something would be lost, and Resume takes you back to it.
The Crossing Well: give gold to the Well together with everyone else. When its cup of 400,000 gold fills, it lights one of seven blessings for the whole server for 60 minutes, online or away: Gatherers', Artisans' or Fighters' Hour, with 20% more XP in those skills, or the Rich, Thrifty, Lucky or Hearty Hour. The Well lists what each one does, and helping fill cups earns its three titles.
Town Tasks: take a task in the square: a stretch of work in a skill, or a hunt, sized to 20 to 60 minutes of your own work. Tasks pay writs and 10% more XP on that work, and every fifth task brings a chest. Spend writs on looks, bank spaces and supplies.
Your task in view: a task you have taken stays on screen under the task card, with how far along it is, until you collect it. Drop this task gives it up if you change your mind.
A living square: click the Well and Town Tasks in the town, or open them from the Menu while you work. Wave, cheer, point or toss a coin into the Well and the others in town see it, or sit down for a while.

Sightings

Something in the world: while you gather, something rare turns up now and then: a Gilded Sprout at the trees, a Gilded Vein in the rocks, a Sunfin at the shore, a Dropped Purse in the districts or a Hearth Flare at the hearth. Click it, or the button on its plate, to claim it.
Boons: a claim is worth about five minutes of your own work at double XP and yield, or ten minutes at triple for a Rare. At the shore it comes as one big catch. Boons stack up to 30 minutes and show as a buff under the task card.
Your choice: set Sightings to On, Rare only or Off in Settings.

Gear and combat

The equipment window: your gear on a new doll with an Ammo cell for the quiver or your spell, every stat beside it, and your Loadout in the same window. Open it with E, from the Menu or from the Gear panel.
One item card: a piece shows the same card everywhere: the bank, the pickers, the Market, the Loot vault and profiles. Hold Shift for the details, and click or press Enter to pin it.
Attack types: gear and monsters now have stab, slash, crush, ranged and magic bonuses, so a weapon that hits a foe where it is weak lands more often. A spell also does more to a foe weak to its element.
The fight sheet: under both health bars: your chance to hit, speed, damage reduction, Auto Eat and food, and what the foe is weak to and resists, as numbers. Every foe's numbers show from the start, bosses and Trials too.
Loot armour: armour from dungeons, the Trials and bosses is now built for damage: 1.8 times the offence of crafted armour, with fewer hit points and half the defence. Crafted armour stays the safe choice.
Removed armour: the armour that training monsters dropped, and the Shadowthread Cowl and Gloves, are gone. Every copy you had, worn, banked, in the Loot vault or on the Market, is paid out in gold at its merchant value, Imbues too, and your Chronicle says what was paid.
Shadowthread: the set is now the Cape and two rare district finds, the Shadowthread spool and bolt, which count for good once found. If you had the Gloves or the Cowl, you already have its find, so no thief loses any of the bonus.
The dagger: a new melee weapon, quick and light, made at the forge beside the greatsword, battleaxe and warhammer.
Overloads: the Everdawn Overload is lowered to seven tenths of its strength. A potion you have already drunk keeps its strength until its charges run out.
Mythic: Mythic pieces are now magenta everywhere, so red only ever means a loss.

Fights look better

Weight: every blow lands with weight, and the foe reels from it. A defeated foe falls with the blow that really ended it, and a Twin Shot's kill waits for its arrow.
Specials: a weapon's special plays as a moment of its own.
The camera: it kicks on the big blows, frames a giant foe and slows a boss's fall.
Finds: a Rare find or better comes down with a beam of light.

Guilds, the Collection Log and pets

Guilds: every skill has a Guild, with over 1,800 tasks from Novice to Expert. Their points raise your rank from Initiate to Prime. Each rank from Apprentice gives a Mastery point, and the ranks bring a crest, a ring, an extra preset, a fourth task to track and a Prime title. What you had already done is counted when you log in. Open Guilds from the Menu.
The Collection Log: five bars: skill levels, Guilds, items, pets and monsters. Each of its nine tiers gives your portrait a frame, the top three a title too, and tiers 3, 6 and 9 add 5 bank spaces each. Only what you got by your own work counts, not what you bought on the Market, and your log is filled in from what you already have. Open it from the Menu.
Pets: every skill now has a pet of its own, 30 pets in all, and they are rare. Your pet follows you in the world and others see it. Choose it, call it or send it home from its cell in the Gear panel.
The token trader: no longer sells pets. A pet you already have stays yours.
Titles: titles are now a real grind: Town Tasks titles come at 100 to 2,500 tasks, and world event titles at 100 of a kind. Every title you already hold stays yours.

Exploration to 120

Four new ways to travel: the ship at level 30, the rune train at 50, the airship at 70 and the star-vessel at 90, each with trips of its own. The ship runs on food, the others on coal or runes.
The Everdawn: a seventh region for Exploration 100 to 120, reached only by the star-vessel.
Goods: every trip now brings home goods that only explorers find, to use or to sell on the Market. The best tools, the strongest potions and the Star Imbue are made from them, and the early goods can stand in for materials at the Store.
Wards, mysteries and Waymarks: wards take you past the hazards of the far regions, seven mysteries tell the story of the Waymakers, Waymarks give perks and luck, and the Hall of finds pays bank spaces at its milestones.
XP: with up to six ways out at once, a trip to Cedar or beyond gives less XP than before, so 99 takes about as long. A region you had already reached keeps paying what it did.

Tools, people and potions

Tools: every axe, pickaxe, rod, sickle, mortar, lockpick and the rest looks new at every tier, up to a new tier at level 100, and from tier 7 they glow. The axe and pick you start with are now chipped flint and river stone.
Thieving: the people of the districts are remade to fit the world, and the guards wear plate.
Herblore: seven new potions: the Wayside Tonic, the Cloudmoss Draught, the Heartwood Draught and the Stormlily Tonic, brewed from explorer goods, and above level 100 the Starborn Artisan's Elixir, the Starborn Overload and the Starborn Grand Elixir.
Weapon tabs: Smithing's weapons, Fletching's bows and Artifice's staffs and wands each sit under one tab, with a strip to choose the type.

Also new

New adventurers: a new adventurer starts with one big Cast button at the shore and a quieter screen, and the tutorial starts on the work itself.
Bank: drag the tabs into any order, Main too, and Sort by category keeps each skill's things together, by level.
Profiles: show the rolls on the pieces someone wears. Press your own figure to open your own profile card. Log out is in the Menu.
The wiki: the Evertrail wiki at evertrailidle.miraheze.org has a page for everything in this update.