Farming Born's Key for Born's Command Set

Born's Key is used for Born's Command Set

This item drop by rare Gravediggar or Brigand. You can farm this through following bounties:

Act 1 - Cemetry of Forsaken - Digger O'Dell
Act 1 - Cemetry of Forsaken - Dataminer

Also look for following rare outside of the Defiled Crypt, when farming the above mentioned bounties.
Act 1 - Cemetry of Forsaken - Lucious the Depraved (Brigand)

Some example pictures below: