"Was that Observation Killing!?"
As the wood chips and dust gradually settled, Borsalino sat slumped against the trunk of a giant tree. The lewd, half-smiling expression on his face had vanished without a trace, replaced by utter gravity and shock.
Observation Killing.
In the world of the Pirate King, once Observation Haki was trained to its peak, its user could suppress their own Haki and presence, rendering their opponent's Observation Haki ineffective. It was an ultimate ability.
This ability, this technique, was known as Observation Killing.
The main reason Borsalino had been unable to evade Tsugikuni Yoriichi's attack was that Yoriichi's presence had completely vanished when he attacked. Borsalino's Observation Haki had been utterly unable to track Yoriichi's movements.
Being unable to sense an opponent's presence was an extremely fatal matter for the strong. If Yoriichi had used the blade rather than the hilt just now, Borsalino would already have been a corpse.
"To master Observation Killing at such a young age..."
"Honestly..."
Borsalino braced his hands against the ground, intending to rise, but the pain in his abdomen drained his strength, and he sank back down.
By then, Tsugikuni Yoriichi had already walked up to Borsalino. He extended a hand and said apologetically, "Sorry, Vice Admiral Borsalino. I just wanted to try out an ability I recently mastered."
"I failed to hold back. Sorry."
Borsalino stared intently at the apologetic Yoriichi for a long while before letting out a breath. He took Yoriichi's hand and was pulled to his feet.
Rubbing the spot on his abdomen that had just been struck, Borsalino could not help asking, "How did you do that?"
Yoriichi knew what Borsalino meant. A technique that concealed one's entire presence, including Haki, was an utterly terrifying ability that would send chills through anyone.
But explaining it...