( Yuuki's POV )
With all of us taking cover behind the pillars in the boss room, the Hydra unleashed its powerful magic, each head of the Hydra had different magical properties and when they fired their different magical attacks the room shook a little but none of us were shaken by it, maybe just Rizu a little.
Yue: Yuuki, I can finish off that beast with one attack, I need time to prepare.
Yuuki: You have it, although try not to damage the body too much, I'm going to need that for later.
Yue began to gather magic from her enormous internal pool and at that moment I emerged from my pillar with my twin sword in my hand, Cecilia flew around the beast but most of her shots or drones did minimal damage that the beast could quickly regenerate.
The Hydra had enough heads to track all our movements and when Rizu and I ran towards the creature a couple of heads launched themselves at us with their mouths open ready to devour us whole, I jumped on its head and threw my twin sword through the Hydra's mouth to pin it to the ground, Rizu mirrored my movements and we ended up on top of two of the Hydra's heads.
I took out my magic guns and fired enough bullets to separate the Hydra's head from its neck, Rizu used a powerful wind blade magic, That cut half of the neck so she used another spell to decapitate the Hydra, I took my twin sword and moved behind the Hydra, There are versions of Hydra that grow two heads when one is cut off and I was preparing for that possibility but it seems this beast didn't have that ability.
I was going to throw my twin sword and at that moment one of the heads turned around and started to rapidly spit out magical attacks, I jumped around in the air to dodge and while I was busy with that Tsukiumi and Yumina made their attack.
Yumina fired a light laser that hit the back of the Hydra head that was attacking me and it exploded into pieces, Tsukiumi activated her IS in her light form and increasing the range of her Katana with concentrated energy she simply flew straight at high speed and she cut off another head.
When only one head remained, Tsukiumi, Cecilia and I fired some powerful attacks, upon receiving those attacks the creature fell forward almost as if it were dead but its magical energy was not diminishing.
I walked forward to extract the magic stone from the creature and at that moment I felt a spike in the beast's magic and a powerful shock wave tried to push me back.
The beast began to move again and its body began to undergo a transformation, Its legs grew long, and its neck shortened, the beast stood on two legs and took on a humanoid form.
The Hydra let out a bloodcurdling roar and used another breath attack, spitting some sort of magical liquid towards me, I dodged but the thing that touched the ground disintegrated part of it and I felt a magical property similar to the one the apostle Noint used, So receiving that direct attack could leave us in a healing capsule for days.
We ran behind the pillars again but the beast grabbed Cecilia from the air before she could get to safety and her IS deactivated under the force of the beast, the Hydra opened its mouth as if it was going to eat her or melt her.
Seeing Cecilia in danger I acted quickly and strongly, activating my dragonewt form, my sage form and my Hollow mask, I flew at lightning speed, I covered my claws with the energy of my Cero and when I swung the Cero shot out in a claw-like form, and the Hydra's arm was easily severed.
I caught Cecilia and then flew behind a pillar, giving her a quick check up she seemed to be unharmed, I breathed a sigh of relief and hugged Cecilia tight.
Cecilia: S-sorry... I made a mistake.
Yuuki: Don't worry, Miss Elite, the battle is almost over, rest here.
Cecilia: Wait.
I was going to put Cecilia on the ground but she stopped me, she activated her IS partially in her arms and she took out her laser rifle, She wasn't ready to give up so I used my tails to tie her to my back and we were ready to keep fighting.
Yue: Yuuki!
Yue called me to tell me that she was ready to attack and she came out from behind the pillar to released her powerful magic, a violent shower of lightning fell upon the beast, breaking and charring part of the beast's scaly skin, that didn't bring down the beast like Yue thought but it did drop to one knee and become vulnerable enough for me.
I flew straight at the beast and Cecilia shot continuously at the beast's chest then I stuck my claw where Cecilia had shot and used a [Gran Rey Cero] that left a hole in the creature, the Hydra fell again but this time I felt its magical power disappear quickly.
When the final boss was defeated we gathered in the center of the room, I stored the Hydra's body in a Thanatos coffin and then another magic circle appeared but that wasn't to summon another magic beast that was a teleportation circle.
The girls looked at me for answers and I walked inside the magic circle the girls followed behind me and what awaited us on the other side of the magic circle was a surprisingly pleasant scene.
We appeared in a circular area with waterfalls around us in a kind of altar and in front of it there was a simple and cozy cabin, we walked there curious if someone was waiting for us.