The lion signifies bravery, nobility, and mastery over anxiety. It symbolizes Goddess Durga’s authority more than the animal kingdom and her power to instill worry during the hearts of evil forces. Though Lord Brahma content with Mahishasur’s devotion for him but he cannot give Mahishasur a boon to become immortal https://www.youtube.com/watch?v=S1HpMpEww4Q