Advancements
There are (...) advancements in Randomness. (...) are hidden.
In-game, they are split in three categories:
Action - for going out there and doing something yourself
Crafting - for obtaining specific items
Discovery - when you experience unique things
Some advancements are in vanilla tabs - marked with [Randomness] In their descriptions.
Hidden advancements are typically absurd or not worth going for. Don't feel bad for skipping out on them.
Action
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Discovery
All Signs To Begone! - Have all three sign advancements below ↓
Master of Closingment - Close a Mushroom Sign
Determination To Leave - Close a Eco-Unfriendly Uranium Sign
Quick Close - Close a Leafwood Sign
Shimmer In The Hole - 
an item
Minetfarc - Uncraft an item
XPlosion - an item into Experience Orbs
Ghostly Dive - Touch Shimmer
Crafting
Perfect Logic - Get RGB Smooth Netherrack
Wit Hour Powahs Combind! - Get all 7 Smooth Netherracks
Too Far Gone - Create and pickup a Eco-Unfriendly Uranium Fence Gate
Not Wide Purple Smooth Netherrack - Get your dirty little hands on a Purple Stone Tool
Good Samaritan - Use the Colools Purge Service
Cover Me In Riches - Wear full Perfect Emerald Armor and have all 5 Perfect Emerald tools in your inventory.
To Infinity... And Beyond! - Craft Infinity
Shine 100 - Obtain an Infinity Star
Multishine - Create a Amethyst Multishard from all 16 Coated Amethyst Shards
Sweet Sweet Sweetery - Create a 4K Sugar from all 16 special sugars
Geminium Getinium - Create a Rainbowinium from all 9 Generic Gems
Perfect Bakery - Create the Megacake
Sip of Chaos - Drink from every drinkable bottle
Opal Banana - Opal Banana
Breakfast Is The Meal Of The Day - Eat a Rotten Flesh Bowl in the morning
Glow Beginnings - Use any color of Glowstick
Light For Everyone! (blue) - Use a blue Glowstick
Automatic Glow Bow (blue) - Manually spawn a blue Glowstick Dispenser
Craft From a Low Glow (blue) - Craft a blue Glowing Gun
Glow From A Distance! (blue) - Use a blue Glowing Gun
Light For Everyone! (green) - Use a green Glowstick
Automatic Glow Bow (green) - Manually spawn a green Glowstick Dispenser
Craft From a Low Glow (green) - Craft a green Glowing Gun
Glow From A Distance! (green) - Use a green Glowing Gun
Light For Everyone! (pink) - Use a pink Glowstick
Automatic Glow Bow (pink) - Manually spawn a pink Glowstick Dispenser
Craft From a Low Glow (pink) - Craft a pink Glowing Gun
Glow From A Distance! (pink) - Use a pink Glowing Gun
Electric Powered Offense - Craft a Redstone Sword or a Redstone Axe
Electric Powered Defense - Craft any Redstone armor piece
Cover Me In Blood Dust - Wear full Redstone armor with every Redstone tool in your inventory
Story (vanilla tab)
Isn't It Wooden Pick - get a Wooden Pickaxe
Isn't It Purple Stone Pick - get a Purple Stone Pickaxe
Isn't It Stone Pick - get a Stone Pickaxe
Isn't It Gold Pick - get a Gold Pickaxe
Isn't It Iron Pick - get an Iron Pickaxe. Not to be confused with the Vanilla advancement.
Isn't It Redstone Pick - get a Redstone Pickaxe
Isn't It Diamond Pick - get a Diamond Pickaxe
Isn't It Emerald Pick - get Perfect Emerald Pickaxe
Isn't It Netherite Pick - get a Netherite Pickaxe
Getting an Upgrade
Breaking An Upgrade - upgrade a Uranium Boat
Isn't It Uranium Boat - upgrade a Uranium Boat to its final tier
Nether (vanilla tab)
A Terrible Fortress
Into Fire
Into Soul Fire - obtain a Soul Blaze Rod
Gallery
Discovery tab.
Action tab.
Crafting tab.
