After telling the Black Pearl's location, the pirates immediately dove underwater to search for the treasure. When the pirates were all underwater, Wolf chanted a magic circle. He summoned a stone resting on the ocean floor, creating an illusion of some sort. Despite being buried in the deep ocean, my system described the rock as a "Black Pearl". It was the prize that the pirates talked about.
Ryoshi rested his head on his extended palm and shook it at each side. Wolf also got him surprised by these peculiar shenanigans, despite being his best friend.
"How come you could create such stones when you literally said before these were rare materials?" I asked, while pointing out the Black Pearl below us.
"I did?" Wolf replied, as if he already forgot the lines he mentioned earlier. "Did I say that? I don't know. Or did I know it?"