After the warning from Calypsa, Pan gathered Talia and the Argonauts to make the journey to Mount Etna. As the Argonauts prepared themselves, Pan turned to his proteges. 

Pan: I must warn you all, I do not know what awaits us. If I know Calypsa, then she will no doubt be prepared for us. Remember what I taught you all. 

Talia and the Argonauts nodded their head. With a smile on his face, Pan teleports himself and the others to Mount Etna where Calypsa meditated. She immediately sensed the Heroes behind her. 

Calypsa: So you've come, Satyr. 

Pan: I have come to end your madness once and for all. 

Calypsa: You always were a short sighted fool. Do you really think you can destroy me? I have become more powerful than any being alive. More powerful than you. 

Midoriya: You underestimate us! We'll defeat you!

Calypsa then chuckles at Midoriya's comment as she got up and confronted Pan and the Argonauts. Her eyes then darted towards Talia. 

Calypsa: You disappoint me child. I had hoped you would see reason. Even after knowing the truth, you still stand by him. 

Talia: Pan's done more for me than you ever have. Mother....please. Let us help you. 

Calypsa: I will not let anything stop me. I will create a world without lies. Nothing will stand in my way. Not even you. 

Without hesitation, Calypsa shot a blast of dark magic towards Talia. Midoriya rushes to her side and blocks it with the Shield of Apollo. 

Midoriya: This ends now!

Bakugo: LET'S FUCKING END THIS BITCH! 

Bakugo then used his Explosion Quirk to launch a powerful explosion towards Calypsa, but she shields herself from the attack. Yaoyorozu then forms the Spear of Virtue while Kirishima activates his Hardening Quirk.

Yaoyorozu: What's the plan, Pan?!

Pan: Bakugo and Kirishima will lay out an all out attack! Yaoyorozu, you and Jiro will provide support while Midoriya and Talia will be with me!

Yaoyorozu: Copy! 

Pan: Argonauts! Attack!

Bakugo and Kirishima began launching a relentless attack on Calypsa while Yaoyorozu and Jiro provided support. Despite their numbers, Calypsa's magic proved nearly too much for them. Pan's magic along with Talia's siren powers proved to be the crucial power. 

Calypsa: Do you really think you can stand against me?! My power is unlimited!

Midoriya then powered up his One For All Quirk and charged at her. Before he could connect the punch, Calypsa repelled him with a shockwave of magic. 

Talia: Midoriya!

Talia then unleashed her magic to pull Midoriya away from Calypsa. As the Argonauts began to be overwhelmed by Calpysa's raw power, Pan and Talia moved in. 

Pan: Stand down Anya! 

Upon hearing that name, Calpysa became enraged. 

Calypsa: Do no utter that name Satyr!

Calpysa then focused her aggression and anger onto Pan. Pan was able to successfully block her attacks. As the Argonauts dragged on the fight, Calypsa began to feel her strength leave her. 

Midoriya: Surrender Calypsa! 

Calypsa: No....no! No! I will not fall to the likes of you! 

Calypsa then unleashes a powerful lightning based attack upon all the Argonauts. The barrage of lightning brings about intense pain upon the Argonauts. Pan and Talia then rush to attack Calypsa. 

Pan: I may have failed you, but I will not fail these students!

Calpysa: Then you will die with them!

As Pan and Calypsa clashed with a barrage of magic attacks, Talia slowly got up from the lightning attack. She looked around and saw the Argonauts incapacitated. She then saw Pan struggling against Calypsa. 

Talia: (Pan!)

Talia then felt a surge of power within her. She then focused her Siren powers into a single devastating attack. When she unleashes the attack, Calypsa was unable to dodge the attack and was sent flying near the edge of the volcano. When Calypsa was downed, the Argonauts slowly got up. Talia then ran to the exhausted Pan. 

Talia: Are you okay Pan?! 

Pan: I'll live. 

Pan then glanced his eyes to Calypsa. He and Talia then walked over to her. 

Calypsa: No....no.....this cannot be.

Talia: Mother....please.....

Calpysa looked at Talia. For a brief moment, there was grief in her eyes. But in an instant, her grief turned to rage. 

Calypsa: No! I won't let it end like this! I will not give you the satisfaction of my defeat!

As Calypsa said that, she spoke an incantation. As she said that, Calypsa's body began to glow with magical energy. She stood up, causing Pan and Talia to step back. 

Calypsa: I will have my vengeance Satyr! In this world of the next, I will have my vengeance!

Calypsa then began laughing maniacally. As Pan and Talia prepared for a battle, the Argonauts gathered around Pan and Talia. 

Calypsa: In death, I will bring about yours! If I cannot bring a utopia to this world, then I will bring about it's destruction!  

Without hesitation, Calypsa jumped into he volcano. Talia was in utter shock as her own mother fell into the volcano. When she did, a powerful wave of dark magic burst from the volcano. What followed was a thunderous roar. 

Pan: No......

Midoriya: What's going on?! 

The volcano then began to violently shake as the roar grew louder and louder. Pan immediately realized what was going on. 

Pan: (Anya.....you couldn't have....) We must get away from here immediately!

Talia: What's happening?!

Pan: I fear Calypsa may have unleashed an evil far greater than her! We must hurry before it's too late!

Pan then teleports himself and the Argonauts to a safe distance. In death, Calypsa had unleashed a true terror.