In "The Pixies' Charge," Valtor is seen holding the box as he materializes in front of the Trix and the pixies during their fight.
In "The Wizards' Challenge," Valtor holds the box as he expresses his dissatisfaction with the current situation between himself and the Winx. He says that he has to remain on the run from his enemies despite all the power contained in the box. He then proclaims that with all the magic treasures he has yet to gather and those already contained in the box, he will prevail over his enemies.
Later, Valtor brings the box containing all his magic power to Lake Roccaluce with him as Faragonda, Griffin, and Saladin gather for the impending duel Valtor challenged them to. Valtor proclaims that he has brought the box as a show of good faith, and that should they defeat him, he will restore the power of all the worlds of which he has drained magic.