Crafting components
Crafting Materials

Diablo 4 has Monster Parts, Ores, Plants, Salvage Material, and Skins for players to acquire across Sanctuary.
Gems

Familiar gems types like Diamonds and Skulls are returning, as well as qualities like Crude and Chipped.
Legendary Aspects

The new Legendary Aspect item can be imbued into another item, transferring a Legendary affix.
Runes?

Blizzard removed Runes from Diablo 4 at launch, but they may make a return in a future expansion or season.
Crafted items
Elixirs

Elixirs give 30 minute bonuses to characters, providing offensive, defensive, and Experience buffs.
Healing Potions

Players can upgrade their Healing Potions at the Alchemist, improving their instant healing amount.
Incense

Similar to Elixirs, Incense also gives temporary buffs, but to all members in the player's Party.
Crafting NPCs
Alchemist

Alchemists around Sanctuary can upgrade your Healing Potions and create powerful Elixirs and Incense.
Blacksmith

The Blacksmith can upgrade an item's base stats and affixes, and also repair and salvage items.
Jeweler

The Jeweler NPC is found in towns and allows players to refine and unsocket Gems, and upgrade jewelry.
Occultist

Diablo 4's new Occultist NPC can extract Legendary affixes from Legendary items, called Aspects.
More advanced crafting system
Diablo 4 ups the ante in terms of crafting unique, powerful items that fit your character and play style. Crafting elements like armor dyes, gems, runes, sockets, and transmog return from past Diablo games. New are Legendary Aspects, which allow players to extract a Legendary affix from a Legendary item and use it to upgrade another item. Also, crafting components will have a special inventory tab.