This part is going to be about Nergal, and while everyone didn't technically fight him (Hector got to kill him after Lowen and Rebecca hurt him), I feel that the fight would be more interesting if I included everyone, since Nergal is a powerful foe, and one of the final bosses. Enjoy!
VS Dark Druid Nergal: Be prepared. You are to be witness to a power that overwhelms all! Those were the words that the Dark Druid spoke as everyone gathered around him, preparing to end this battle, once and for all...
Lowen, Rebecca, & Raven: The trio were the first to strike. In a display of their amazing teamwork, Lowen braced his spear against the ground, giving Raven a boost and throwing him behind Nergal. Lowen then charged with his Rex Hasta and Rebecca unleashed a Rienfleche shot. Raven pulled his Regal Blade from its sheath in midair, and came down upon Nergal with an enormous slash on Nergals back, at the same instant that Lowens spear tore into his side and Rebeccas arrow pierced through his arm, giving him no chances to dodge the onslaught. Nergal, injured but far from dead, blasted the three of them with his mighty Ereshkigal, which felt as though it were sucking away their life. They were left exhausted and breathless, but they survived the ordeal, and they were not alone in this endeavor.
Dorcas: He followed after Lowen, Rebecca and Raven, and slammed the Basilikos down as hard as he could upon Nergal, tearing a gruesome hole in the robe and cutting into Nergals chest. Just like the others, he was sent flying back, and felt devoid of most of his energy, also noticing that the wounds they had inflicted on Nergal were closing somewhat. Nergals wounds weren't healed entirely, but he knew that this spell was the only reason he hadn't fallen to their attacks yet, as the wounds were no longer fatal. He could no longer stand, but he saw the remaining people preparing to strike, and knew they would win.
Jaffar: .....
Hmph... It's you, Jaffar? Turning your sword against me, your master? Do you forget who raised you? You are worthless.
...Wrong. I am a man.
Oh, really? If so, then I will give you a man's death!
Jaffar charged forward, straight into the life draining magic that Nergal had cast, and he readied his Killing Edge, aimed at Nergals throat. His energy was fading, but his momentum carried him forward, and he appeared out of the shadowy storm of magic, landing, and then unleashing a powerful uppercut that tore through Nergals arm. Jaffar then pulled back, knowing he could no longer fight, and also knowing there were others who could end this.
Renault: ...Nergal, do you remember me?
Hah. You are... Renault. So you're still eeking out a wretched existence?
I went astray. I listened to your honeyed words... I dreamt of the impossible... the return of a lost soul. But... what you gave me was... a puppet... It was soulless, nothing more than an empty vessel!!
Just an empty vessel... Isn't that what you wanted? You desired to bring back your dead friend. you were my experiment, and I completed my morph. I'm grateful, Renault. Thanks to you, I gained power.
You villain... You cursed him! Your crime can never be forgiven! I will end this with my hands. In the name of my lost friend!
Renault knew of Nergals power, and he also knew how to avoid it. Dodging away from the epicenter of the spell, he then unleashed two blasts of the Divine tome he wielded, marginally wounding the fiend, but not doing any notable damage. He knew on his own he would have failed, but there was still one more who could finish this...
Hector: Nergal!
I cannot understand you, Hector of Ostia. Why would you do all of this for Eliwood? Is this miserable thing called friendship really worth dying for?
I don't expect you to understand. You've forgotten what it means to be human! Nergal! My connection to you... it's over! I'm finishing everything up right here!!
Hector felt the might of the Armads axe he wielded roaring within him. He knew this next blow would finish it, and he struck with all the force he had. A powerful vertical slash ripped straight through the Dark Druid, nearly bisecting him. He lived long enough however, to utter these final words...
Why? Why must I lose? More power... I must be stronger... I... Why? Why did I... want power? Gaa... Not like this... I will not die...like this. With my last breath...tremble...and despair. Hwah ha ha... Ha... ha ha ha...
Suddenly, a loud rumbling could be heard from up the stairs. Athos quickly healed everyone with the Fortify staff, and they all headed up, and no stared dead on into the face of calamity...
