But the magic love-potion had been mingled with the draught, and no sooner had he set down the horn than the likeness of Brünhilde faded from his mind, and all memory of his love for her became a blank. It seemed to him that the fair Gudrun was the first maiden he had ever beheld, and a passionate desire to possess her suddenly grew up within him.
Gudrun beheld his ardent glances with great joy, for an answering love had quickly sprung up in her own heart for the noble hero before her. Taking her willing hand in his, Siegfried led the maiden, who now possessed his whole heart, to her royal brother, and eagerly requested her hand in marriage; and to this Gunther gave his consent on condition that the Valkyrie, Brünhilde, was secured as a bride for himself. Siegfried gladly agreed to go through the fire once more, and woo Brünhilde for his new friend; and when the two had sworn an oath of brotherhood, they set out together to begin their enterprise at once.
In a royal barque they sailed down the Rhine a certain distance, and then when the Valkyrie's rock came in sight, Siegfried bade Gunther remain in the boat, whilst he himself went forward alone to climb the mountain. By means of his Tarnhelm, or wishing-cap, he took on the form and appearance of Gunther—the two having agreed that the martial maiden must be wooed and won by Siegfried in the likeness of the king—and promising to be loyal and faithful to his oath, the young hero began to climb the rocky height.
Brünhilde had just received a visit from her Valkyrie sister, Valtrauta, who had come to entreat her to restore the Nibelung's fatal Ring to the Rhine nymphs once more, as the only remaining hope of saving the dwellers in Asgard; for Wotan had now gathered the gods together in Valhalla—around which he had caused to be piled a forest of faggots from the world's ash-tree, hewn down at his command—and all were silently and sadly awaiting their approaching doom, the dreaded Twilight, that meant for them destruction. The only glimpse of hope now left was for the mighty Ring to be returned to the Rhine, when its curse upon men and gods would become void; and on learning this from the beloved All-Father, Valtrauta had mounted her war-horse and flown at once to her fallen sister, who she knew possessed the Ring.
But Brünhilde, cut off as she was from the joys of Valhalla, would not part with her love-token, which was more precious to her than all the dwellers in Asgard; and in spite of the passionate entreaties of Valtrauta, she utterly refused to give up the Ring.
Finding that her pleading was in vain, the despairing Valkyrie was compelled to depart; and no sooner had she gone, than Siegfried, in the form and garb of Gunther, sprang fearlessly through the zone of fire, and advancing towards Brünhilde, whom he regarded as a stranger, announced calmly, in a disguised voice, that having braved the flames he had come to possess her as a bride.
Full of horror at being thus wooed by a stranger during the absence of her hero-lover, Brünhilde shrank back, and indignantly refused to yield herself to this bold intruder, receiving strength from her magic Ring; but upon her talisman being wrested from her by the superior force of Siegfried, she became powerless, and was compelled to submit to his will. Siegfried now led her to the cave as their bridal chamber, but, mindful of his oath and loyalty to Gunther, whose wooing he had so strangely undertaken, he laid his sword, Needful, between them.
Next day, at dawn, the disguised Siegfried took the bride he had won for another by the hand, and led her safely through the flames and down the mountain-side, and on being met at the river-side by Gunther, he instantly vanished by means of his Tarnhelm, and transported himself to the Gibichungs' Hall. So when the true Gunther took her by the hand, Brünhilde regarded him as her wooer of the night before, and the pair entered the barque.
Now, during the absence of Gunther and Siegfried, Hagen had been visited in a vision by his gnome-father, Alberic, who besought him to seek quickly an opportunity to kill Siegfried, and so secure from him the magic Ring by means of which the Nibelung might regain his lost power; and Hagen gladly agreed to use his craft for this purpose.