Legendary and Exotic gear can be infused with Rare, Legendary, or Exotic gear of a higher Attack/Defense value.
Infusion will increase the Attack/Defense value of your preferred gear.

These items must be:

• The same Armor/Weapon category (Primary Weapon, Helmet, Ghost Shell, etc.)
  
• Year 2 Armor/Weapon (look for the Taken King logo in the upper right corner of the item icon)
  
• Unequipped
  
• Unlocked
  
• In your Inventory (Items must be taken out of the vault in order for them to be available for infusion)

Infusion requires some or all of the following:

• Glimmer
  
• Weapon/Armor upgrade materials
  
• Mote of Light OR Exotic Shard*
  
• Legendary Marks

*Infusing into a Legendary weapon/armor requires a Mote of Light, while infusing into an Exotic weapon/armor requires an Exotic Shard.

For Year One Weapon/Armor Ascension, please follow this FAQ.