DxD: Ascension - Redux

Chapter 10: Overboost

BGM: Persona 5 - Restlessness

"...So that's the plan?" Asia asked.
"Yeah," Zach confirmed. He summoned his copy of the Boosted Gear. "Ddraig talked to me through this thing. He told me about how Issei could easily gain more power, but with a cost. Ddraig, why don't you tell her yourself?"
Ddraig's voice boomed out of Zach's Boosted Gear. Of course. In his current state, Issei is too weak to use his Balance Breaker normally. However, if he sacrifices something, I can give him the ability to use an incomplete Balance Breaker for a short time. Only until the count of ten. Using that, he should be strong enough to beat Riser, he explained. Provided he can do it within the limit.
"What'll he sacrifice?" Asia wondered, looking at Issei, who started to slowly wake up.
"Ugh... my everything... Rias?" Issei sat up, rubbing his eyes. "Oh, Asia. And Zach... what're you two doing here?"
"We were told by Grayfia that she and Rias's brother set up a way for you to get to the engagement party and stop Rias from marrying Riser. It won't be easy, and you'll technically lose a limb, but you'll get your chance to stick it to him. You up for it?" Zach challenged Issei.
Issei fist-pumped, with a determined look on his face. "Of course! What's the plan?"
I can give you the strength to beat Riser using your Balance Breaker, Ddraig began. But I'm going to need you to sacrifice something in return. You'll have to give me your left arm.
"Wait, what?! What'll happen to it?" Issei asked.
It'll be replaced with a dragon's arm. Your more powerful allies will be able to remove some of the power to make it look like your normal arm afterward, though.
"Oh... well, that's good." Issei sighed in relief. "Wait! I just had an idea to make Riser even easier to beat! Asia, do you still have a cross and some holy water?"
Asia tilted her head to one side in confusion. "I do. Why?"
I see where you're going with this, partner. If you touch holy objects with your dragon arm, you won't be affected as a normal devil would. However, Riser Phenex would still be harmed just as badly as any devil. It seems like I underestimated your intelligence. Well done.
Asia's eyes lit up as she understood the plan. "Zach, you won't be as affected as we are by the holy objects. Can you come with me to get them?" After receiving a nod from the fallen angel, the two went to her room to get the items before coming back.
"Here." Zach set the cross and holy water down on the bed.
Issei took a deep breath. "Alright Ddraig, I'm ready. My arm is yours." His left forearm and hand glowed red, with a green jewel forming on the back of his hand. The Boosted Gear formed over it, in the new form that it had taken during the Rating Game. "Moment of truth..." Issei muttered, reaching out to touch the cross. He closed his eyes as his left hand closed around the necklace's pendant, expecting to feel severe pain. But the pain never came. "It worked!" Issei yelled triumphantly.
A silver magic circle formed on the floor. Grayfia rose out of it. "Well done. I was going to inform you of Lady Argento's holy items, but it appears you figured it out yourself. At any rate, you have just one chance to stop Riser from marrying Rias." She held out a small paper with a magic circle drawn on it in red ink. "Use this to instantly be transported to the engagement party, where you'll meet the rest of your friends. I wish you good luck." Grayfia bowed, then disappeared back through her magic circle.
"Well, this is it..." Issei said. "I'm gonna get changed, then I'll head out."
"One last thing," said Zach, stopping him. He stepped closer to Issei and touched his right hand. "There. As soon as you activate your Balance Breaker, that'll activate a Phoenix's Blessing. It'll make you less vulnerable to fire until your Balance Breaker runs out of time. You've got one shot at this, Issei. Make it count."
Issei looked at his right hand. An image of a royal blue bird appeared on the palm. "Thanks! Now get outta here so I can change in peace."
Zach and Asia left the room. Issei changed into his school uniform. See you guys when I get back... with Rias, he thought. After mentally saying his goodbyes, he clutched the paper Grayfia gave him. A magic circle formed under his feet, and he was gone.