W. Va. Code § 36-4-3: Special warranty.

A covenant by a grantor in a deed "that he will warrant specially the property hereby conveyed," or a covenant of like import, or the use of the words "with special warranty" in a deed, shall have the same effect as if the grantor had covenanted that he his heirs and personal representatives will forever warrant and defend the said property unto the grantee, his heirs, personal representatives and assigns, against the claims and demands of the grantor and all persons claiming by, through, or under him