As planned, Yinn was the first to enter the second basement and with her invisibility cloak as well as the hovering module, there was nothing to worry about. She slowly but surely passed through via the ceilings of the basement and she already saw silhouettes of the Royal Assassins standing by at the certain crevices of the basement.
It was as if the entire Bearling Palace had been built in such a way that the Royal Assassins and Guards had places they could hide and ambush their enemies. Surely, this was probably due to the fact that people had been invading the Empire multiple times that such a defensive feature had been installed.
Of course, it would be a dual edged sword for the people working there too since if people can hide in a defensive battle, enemies too can do the same. Yet, if they had continued to keep this meant that it had been effective for the Royal Assassins and guards for centuries that they maintained it that way.