Rule 21 . Complex Litigation. Complex litigation means:

Potentially difficult or protracted action that may involve complex issues, multiple parties, difficult legal issues or unusual proof problems. In the event an action is not filed as a complex litigation, the court may, after giving notice to all parties, designate the action as a complex litigation and order that the filing fee/answer/appearance/fee for complex litigation be tendered to the Clerk of the Court within thirty (30) days.