Why You Need It

Only required for orange equipment.

Best Way To Get It

You get a lot of materials during normal game play, but you might still find yourself short when wanting to forge pieces. What the best way is to get materials also depends on the various credits you might have, price wise there is not a very strong preference.

Other Ways To Get It

You get the materials from bonus barbarian chests and from most of the (seasonal) events, and you can buy them in various shops.

Keep In Mind

These materials are only required for simple equipment that you will replace eventually. Probably still worthwhile to spend credits on, but you might reconsider if you are close to making gold equipment.

Shop Availability

Feedback?

I am trying to keep this as correct and complete as possible, but if you notice any mistakes or missing information, please let me know by leaving a comment below.