The Compendium phases unpredictably between corporeal and ethereal states, its translucent pages flickering with accumulated arcane knowledge from across all ten realms. Spectral fragments of text and diagrams orbit around its core, whispering fragments of forgotten spells and realm-specific techniques to those deemed worthy. Its luminescence intensifies when multiple league energies converge, drawing power from the very conflicts it seeks to document and preserve.

It serves as the eternal guardian of wielder legacy, intervening during critical moments to share crucial knowledge that prevents catastrophic magical failures during cross-realm events.