General P.O.V
'Shred, Benihime'
Countless crimson needle-like projectiles were fired from the barrier at an intense speed towards Ancient One which she couldn't possibly dodge even if she could see the future.
She used one of the most basic but the most versatile spell of a sorcerer who uses Eldritch magic i.e. creating a portal in front of her.
The needles went through the portal without a single one harming her.
"Using these magic portals in a spar should be banned." Law grumbling to which Ancient One smirked and said "Says the one who can teleport himself in a moment's notice."
Law did not know how to reply to that so he just continued attacking her with flying crimson slashes.
Ancient One again tried to create a portal in front of her but Law used shambles and teleported her towards another incoming slash.
She hurriedly created barriers from her magic which broke one after another but since she was drawing power from dark dimension, the barriers were strong and she managed to block the slashes but in turn used a lot of energy. She was panting as she was quite tired from the energy drain.
Law although not as tired was not any better as he used quite a lot of stamina/energy to teleport her as she was using magic to protect herself from this.
Ancient one created two tao mandalas and launched them towards him.
They tried to cut Law into two but he tried to dodge it but the tao mandalas continue to follow Law.
'They are like Krillin's destructo disks. Jeez, that's some nostalgia.' Law mused to himself as he covered Benihime in haki and slashed both the tao mandalas into two. The disks disappeared after that.
'Lets turn it up a notch. Hado #23...' Law was about to use a strong spell but was interrupted by Ancient One.
"I give up." Ancient One declared with a sigh which flabbergasted Law as he could not understand why she would give up this easily.
"Huh? But why?" Law asked
"You have clearly proved your strength. Besides I can see you still have a lot of energy and stamina in your tank but I am quite spend. Although I can use the eye of agamotto but using one of the infinity stones in a spar would not be beneficial at all." She told her reasoning for giving up to Law.
Law pondered about her reasoning and realised she could have done much more in the fight if she used the powers of the time stone. She could have trapped him in a time loop like Strange trapped Dormamu. He didn't have a way to counter that. He shivered at the notion of that.
He also has a ridiculous thought about the powers of his devil fruit. He wondered if he could control the time in his ROOM since his devil fruit technically is supposed to control everything inside the room.
'Well, something to experiment on later.'
Another thing he realised was that his devil fruit powers gave him an advantage over Ancient One. She could not control the things in the mirror dimension thanks to the room which greatly limited her strength.
She could have launched more stronger spells but he could just teleport out of the way using his devil fruit powers.
'I bet she even used some kind of space barrier to restrict or block my teleportation but since my ability does not come from magic, it didn't work on me. I would have been in a lot of trouble without my ability to teleport instantly.' Law thought
While Law was thinking about all of this, Ancient One spoke up again "But this power is not enough to face against Dormamu. He is a cosmic being and you would be fighting him inside his home."
Before she could continue about more dangers of facing Dormamu, Law in a confident tone said "You don't have to worry about it. I have a Trump card against him."
Law's trump card against Dormamu was actually quite simple. It was his astral projection which was this world's soul form.
The God who teleported him in this world had sealed all the spiritual pressure within his soul and body so it doesn't leak out and crush everybody near him while at the same time making his body able to use all the Shinigami powers without a soul form.
But Law figured out a way to use his spiritual pressure. He would do it just like how a shinigami uses his/her soul form while leaving their body by using astral projection and going to the dark Dimension.
Yes, his power would remain the same but the soul pressure in itself very deadly. Not only would he be able to pressure Dormamu and maybe even scare him out with his spirit pressure, he might even be able to harm him a little.
Besides the soul pressure of an isekaid individual with Urahara Kisuke and Trafalgar Law powers was sure going to be a hella strong. Heck, Kisuke was one of the strongest Shinigami there was.
He did not have to fight Dormamu. He had to take Ancient One's soul away from him so that she could use her powers freely without losing immortality and getting weakened against Dormamu.
He couldn't wait to bully Dormamu and complete his deal with ancient one. Then he would finally be able to learn magic.
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