S1·E143 The Miracle of Life

Leo uses Life Stream Dragon to counter Asterisk's, and Fortissimo's damage effects, and to restore everyone's life points to 2,000 (not including Aporia), which puts Luna out of the danger of dying. Seeing that his efforts to inflict damage to the Signers has failed, Aporia gets really agitated. Aporia then activates a trap to prevent Synchro Monsters from attacking, but Luna uses Ancient Fairy Dragon's ability to destroy his field spell, and activate one of her own that supports Synchro Monsters, allowing Jack to bring out Scar-Red Nova Dragon. The destruction of Fortissimo causes the fortress' structure to shake violently, and begin to collapse. Aporia manages to bring out Machine Divine Emperor Mechanicle Infinity Cubic to increase Asterisk's attack points, but Leo and Luna use their traps and dragons' abilities to weaken it. Jack then destroys Asterisk by attacking with Scar-Red Nova Dragon, which defeats Aporia, who falls to his "doom" with a feeling of hope in his heart.