Advanced item creation is used to create new items from base materials. There are advanced techniques for each of the major methods of item creation (Crafting, Smelting, and Brewing).
Advanced crafting requires an Aeon Forge. Also known as an advanced crafting table, the Aeon Forge, with its 5x5 crafting grid, unlocks many new crafting recipes, including specialized weapon and armor recipes (see Weapons and Armor). There is also another type of advanced crafting, called legendary crafting, which is a 3D 7x7x7 grid. Items crafted using this have slightly more pixels than a normal item.
Advanced smelting requires a Crucible. This advanced furnace allows you to combine base metals to make alloys (such as Black Bronze and Endersteel), which are much stronger than metals that are mined right out of the ground. The Crucible is often used in conjunction with the Aeon Forge to make weapons and armor from powerful alloys.
Unlike advanced Crafting and Smelting, advanced Brewing requires multiple items, all of which are attached to an ordinary Brewing Stand to increase its capabilities. The known items are Diffusion Helixes, Vacuum Matrixes, and Elementifiers. As of now, their purpose is unknown, but it has been revealed that advanced brewing can be used to make some of the most powerful potions available (like a Spellcrush potion).
Some may also require ice, to cool the potion down, as opposed to blaze powder, to heat it.