@Notes:
With large changes to difficulty scaling, you can expect more defensive options in both Mastery and equipment in the future
@Achievements:
Adjusted some values on the stat Achievements "Elemental Master" and "Elementalist"
@Anomalies:
Some small Anomalies have been made a bit larger
@Area Layouts:
Adjusted many odd spawn locations of doors in Act 2 and Act 3
@Balance:
Melee classes (Berserker & Templar) now take a flat 30% less damage from all sources to compensate for their need to be closer
Mastery exp requirement has been increased, particularly after reaching over level 300
@Companions:
Idle companions now target the monster the player attacks
Companions now slowly regenerate health when not in combat
Companions now copy player resistances, with a minimum of 0% (can't go into negatives because of difficulty penalty)
Companions can now receive "damage reduction" from special items, lowering their total damage taken
Companions now also mirror the player's "crit damage" stat
This means that the following stats are now transferred to companions:
Crit chance
Crit damage
Movement speed
Resistances
Damage and Health based on listed skill values
@Difficulty:
Completely rebalanced to better suit the new skills and Mastery systems - some tweaking is likely needed
Difficulty now scales more steep, especially from Legendary and up
However Casual difficulty should feel a lot more Casual now, too
Anomaly difficulty is highly affected by the changes, and you will be lowered to Anomaly 50 if you have made it further
Anomaly Level 200+ roughly translates into what was previously 1000+
Monster extra affixes has been capped at 6 for Champions and 5 for Elites, and are now more consistent through the difficulties
@Enchanting:
Scrambling and freshly generated items now properly follow the same set of rules. These rules have been updated to the following:
Rings and Amulets must always roll an additional enchant, this additional enchant is always an Epic enchant
Weapons, Armor, and Boots have a 25% chance to replace one of their Major enchants with an Epic enchant.
Scrambling Weapon, Armor, or Boots, may replace the Epic enchant with a Major, and vice versa. You can only roll one Epic enchant per item.
You can now enchant directly from your equipment rather than only from the inventory
You can now also Augment (lock) enchants that have rolled their maximum value
There is now a full index of all possible enchants when you hover/inspect an item placed in the enchanting slot
Enchanting materials no longer drop until you finish the Missing Codex quest, and Chantie will tell you where to find them when completing the quest
The "Chance to burn on hit" and similar enchants are now using percentages, making it scale much better in endgame. These enchants can now also be Augmented very high. The old versions have been made absolete.
Bleed enchants now use "Bleed Damage" instead of Physical damage, ignoring enemy resistances and relying on the "Bleed Damage" stat.
Health Injector power can be augmented a little higher
@Equipment:
Added 2 new True Legendary items:
Life Guard
Unbreakable Bond
Added new powers to the following Legendary items:
Berserker:
@Brutal Stompers
@Firebreather (previously known as Cataclysm)
Warden:
@Forest Embrace (was previously not exclusive to Warden)
@Packleader's Vest
@Storm Pendant (previously known as Stormcaller's Pendant)
Warlock:
@Infernal Horns
Updated Set:
Sun & Moon: now buffed to be more useful and an endgame alternative for mixed fire/frost builds
Updated Power:
Golden Guard: Now deals thorns damage as holy damage in the form of holy bolts (does not replace thorns), rather than just flat holy damage
Nature's Barbs: Now also turns Thorns into Poison damage
Tweaked drop rates of True Legendary items (they are now separated from regular Legendaries in their own loot pool)
Updated names and base enchants of many items
Lowered level requirements of several Legendary items
@Interface:
Added support for tiny healthbars that are always visible - check the Interface menu to toggle "Display Enemy Healthbars"
Player Overhead Healthbars and Companion Overhead Healthbars are now also tiny
You can now also toggle companion nametags on or off regardless of healthbar visibility
Champion, Elite, Unique, and Boss monsters have been given slightly larger healthbars with a golden accent
"The Name Tag Scale" option is now a "Healthbar & Name Tag Scale" option, allowing you to adjust the new healthbars
Damage Number, Text, and Name Tag scaling sliders now scale to each 10% rather than each 100%
Empty skill snows now have a "+" icon on them to make it more clear they are selectable
You can now hover on your skill bar to get your selected skills' info rather than having to enter the skill tree to check
You can now also hover the skill notification icons for a text notice, and you may also click to open the skill trees
You can also hover the experience bar for exact details on your experience and mastery experience
Player healthbar now gives off a shine when below 30% health
Added a new option to enable cooldown numbers on your skill bar
Mouse over will now prioritize enemies over loot so you don't get loot tags or pick up loot in combat when trying to attack
The bag slots now have bag icons on them & the belt slots have potion icons
Added a dark background behind portal names so they're easier to read
@Killstreaks:
Now awards more Crystals, and exponentially increases with large streaks!
Now also awards some more experience, depending on difficulty and size of streak
@Misc:
Crystals now shoot out of chests and monsters in a rapid stream rather than all at once (I just thought it looks neat)
Improved load times in some large forest areas
@Monsters:
Putridus: Now always drops a 4 slot pouch
Thorns and DoT effects now deal a maximum of 10% of the player's health
Explosive monsters can no longer kill the player in one hit, and will at the very most deal 50% of their health (non-champion monsters deal much less)
Mana leechers now drain a maximum of 5% mana per hit
Bosses now drop more Crystals
@Quests:
Protect And Serve: Now rewards a 6-slot bag in addition to the helmet
@Skills:
General:
Projectiles should no longer count breakables as hits and trigger effects / proc / spend hits
Berserker:
Rime: The Use effect now adds a % of Frost damage into Chill damage per hit, rather than set values
Dragon Stomp: Slightly reduced range
Templar:
Hallowed: Now has a range modifier which is affected by the Reach stat
Blaze: Now triggers "on hit" effects and passives
Pyre & Ember: Lowered screen shake from these skills
Holy Fire: The Use effect now adds a % of Fire damage into Burn damage per hit, rather than set values
Star Struck: The damage radius is now affected by the Reach stat
Warden:
Multishot & Volley: Chance to trigger splinters & overdraw is now independently calculated for each arrow
Warlock:
Screaming Skull: No longer damage foes through walls
Infernal Demon: Now affected by Companion stats
@Sounds:
You can now set the maximum amount of sounds to be played simultaneously in the Audio options
@Stats:
Base Health Regeneration and base Mana Regeneration now scales much faster as you level up
Added a damage reduction stat, which will reduce all damage after resistances. Templar + Berserker has 30% damage reduction. Special items may increase this value!
There is also a special damage reduction stat for companions, which can be increased by special items
Blockrate is now capped at 75%
Damage blocked is now capped at 50%
@Tinka's Domain:
Added an Enchanter NPC to this area
@Fixes:
Fixed several instances of the Forest areas generating unreachable areas
Fixed some problems with the statistics calculations of experience gain and experience loss from deaths
Fixed several problems with enchanting scrambles
Fixed Berserker's "Hotfooted" not working
Fixed auto-targeting spells targeting invulnerable  or spawning (also invulernable) foes
Fixed "on kill" effects not triggering from foes who died of DoT effects
Fixed not being able to use the analogue sticks when creating a new hero
Fixed issues with analogue sticks and sliders in option menus
Fixed issue where connected but unused controllers could be used to pause game and change settings, making it possible to get unresponsive menus 
Fixed issues with getting large amount of experience points at once and it not correctly carrying over into the next levels' progression
Fixed an issue with the calculation of Combustion damage with the Burning Hells set
Fixed Flashfire being considered a Sorcery spell instead of the intended Bane spell
Fixed Achievements "Elemental Suppression" and "Doctor Huu?" not triggering
Fixed issue where champions didn't improve their Shadow resistance, but did for all other resistances
Fixed issues with temporary companions like Wisps, Clots, Living Blood, and Demon Lord set bonus hounds not properly being affected by companion bonus stats
Fixed buff typos
Fixed item name & description typos
Fixed bad wording on some skills
Fixed issue where Storm Mender had their heals improved by the players Lightning damage
Fixed damage falloff calculation for Explosive monsters (the further away you are the less damage you take)
Fixed issue where you might get stuck in some animations
Fixed issue where Leap and similar skills sometimes wouldn't deal damage
Fixed "Blizzard" not slowing foes
Fixed draw height of Nimbus clouds
Fixed errors on affix calculations based on difficulty
Fixed hero select screen being imprecise about character versions
Fixed boots "Boots of Hermes" and "Nimble Boots" not showing their special enchants in the enchanter (not retroactive, you will need a new pair for the effect to show up)
Fixed several issues and crashes in multiplayer which could occur when a player enters a portal with one or more players navigating their inventory menus at the same time
Fixed menu "blip" sound being played several times when pausing the game
Fixed issue where doors to new areas sometimes wouldn't be generated