RDM Artifact Armor +1 Quest. Here is what you need, once for each piece of equipment:
• The piece of equipment you're upgrading
• This item, from Temenos
• Cardinal Cloth, from Apollyon
• Rainbow Velvet or Tiger Leather, crafted
• 15, 20, 25, or 30 Ancient beastcoins
The last two depend on the piece of equipment you want to upgrade.