The Caja Metálica de Estaño first appears in Volume 2 as a small, silver-plated rectangular tin box with carved patterns and a heavy, austere appearance. Throughout the series, this seemingly ordinary container becomes a vessel of profound significance, its metallic surface hiding layers of mystery that connect to the deeper lore of the world. Its evolution from a simple object to a key element in the unfolding narrative reflects the series' theme of hidden depths beneath mundane exteriors.

The Caja Metálica de Estaño first appears in Volume 2 as a small, silver-plated rectangular tin box with carved patterns and a heavy, austere appearance. Throughout the series, this seemingly ordinary container becomes a vessel of profound significance, its metallic surface hiding layers of mystery that connect to the deeper lore of the world. Its evolution from a simple object to a key element in the unfolding narrative reflects the series' theme of hidden depths beneath mundane exteriors.