"So the dungeon of Pebble Castle is a Crypt. No wonder I couldn't find it."
Even if Leech had tried to dig his way in from outside the castle, he never would have found the dungeon, because Pebble Castle doesn't have one.
Leech didn't know where Crypts came from, but he knew they were independent spaces. The original Leech had possessed the ability to capture these spaces and establish them near himself.
'So this Grand Sorcerer must have stumbled upon the Pebble Castle Crypt by accident, and he very likely found something valuable inside.'
But the red dot indicated that the Grand Sorcerer had only found the Crypt; he didn't have the ability to claim it for himself.
Leech had considered the possibility of others entering Crypts long before this.
For example, the handsome and alluring Guy Marvin had become a Transcendent only after accidentally falling into the Water Nymph's Crypt and receiving the nymph's blessing.
