W. Va. Code § 56-4-20

In like manner, if good cause therefor appear, and there be no unreasonable delay on the part of the plaintiff in applying for such order, the court or judge in vacation may order the defendant to file a more particular statement, in any respect, of the nature of his defense, or the facts expected to be proved at the trial, which statement shall be under the oath of the defendant, or some other credible person, to the effect that the affiant believes the same will be supported by evidence at the trial.