From The Heroes of Might and Magic III wiki

This is a combination artifact.

Combination artifacts were introduced in the expansion Shadow of Death,
and are only available when it is installed.

At the beginning of combat (first time one of your creatures are active), it will cast the spells Slow, Curse, Weakness and Misfortune on all enemy troops, for 50 rounds. The combination of artifacts also gives +3 to Attack and Defence skills and +2 to Power and Knowledge skills.

Requires the following artifacts to create:

• Blackshard of the Dead Knight
• Skull Helmet
• Rib Cage
• Shield of the Yawning Dead.

You cannot purchase combination artifacts in Artifact Merchants. Cost is derived from sell price.

Basic Cost: 60000 gold

[edit] Comments

It's stated that the Armor also casts Disrupting Ray. This is bogus, however. Cid SilverWing