Crafting
Talismans and Charms
A Seal in the centre, Charms around it, set bonuses on top.
Unlocking it
The Talisman opens during the Lord of Hatred campaign, in the quest The Last of the Horadrim. In later seasons it is available as soon as the campaign is done.
Seals
The Seal sits in the middle of the Talisman. It decides how many Charms you can fit, how many of those may be Unique Charms, and adds affixes of its own.
Mythic Seals
Charms
Charms fill the ring around the Seal and come in three kinds.