: Pieces move in straight lines like Rooks but can jump between the ground and Skyboard tiers [25, 28].
Are you writing about the within the Codex Alera universe? Ludus-CODEX
However, "Ludus" and "Codex" are also significant academic terms in and Media Theory , where the "Ludic Codex" (or "Ludex") refers to the intersection of book-bound media and digital play. 🏛️ The Ludus of Codex Alera : Pieces move in straight lines like Rooks