Artifact Merchant — Airship Shop

Artifact Merchant sells hero artifact fragments. To open this Shop, tap Merchant at the bottom of the Airship page:

Alternatively, you can open the Shop by selecting the desired artifact and pressing Find next to Merchant.

Here, you can spend 400 Artifacts Coins to purchase any necessary artifact fragment.

Note
Unlike Artifact Weapons, books and rings are not unique artifacts. For example, Defender's Covenant is not exclusively Astaroth's artifact. You can use it to upgrade Cleaver and many other heroes.