"Advanced observation haki?"
Sengoku's expression changed instantly. He knew that if Shane achieved another haki breakthrough here, he would only become more terrifying in the New World.
Over the years, few pirates had honed all three types of haki before heading to the New World.
If he advanced two of them to advanced techniques, he would only become more troublesome!
"What? When did you learn that?"
Kaido was stunned too.
He had thought Shane's talent was already astonishing: he had only just mastered advanced armament haki, then grown more proficient after fighting Black Tanuki.
He had never expected him to achieve a breakthrough in advanced observation haki without a word!
"To be precise, this is a technique similar to Black Tanuki Pupil."
"By combining my fruit ability with my body's structure, I concentrate observation haki in my eyes."
"That lets me hear other people's heartbeats and see subtler weaknesses and possibilities!"
Shane's eyes turned into Purple Pupils, yet they instead allowed him to hear other people's heartbeats.
In truth, Purple Pupil was an outward manifestation. Its essence was highly concentrated observation haki, achieved through the properties of the Paw-Paw Fruit.
Then, relying on his powerful, resilient body, he allowed his brain to handle more computation.
Ultimately, what he called Purple Pupil was actually a distinguishing feature.
Just as Shane had said, it combined haki and a Devil Fruit, like Black Tanuki's Black Tanuki Pupil.
It produced an entry-level form of advanced observation haki.
That was why Shane could hear other people's heartbeats, but not their thoughts.
Even so.
He had at least knocked on that door.
"Don't fool me. Your eyes can hear heartbeats?"
Astonishment was written all over Kaido's face.
He had thought that seeing through the physical manifestation of conqueror's haki after a brief clash with Sengoku proved