'Whoever made these pillars, why do they not put any surveillance type of formation?'
Some formations would put surveillance type of formation so that the one who made it would know if their formation was broken or had any problems. After all, some formations were special and this kind of formation that Riya saw was also the same.
But Riya didn't see any.
This might also be because the person who made the formation was confident in their skills that even if some people were to take advantage of these special magic cores, it would not affect them too much.
But either way, Riya was glad that there was no surveillance or detection type of formations set up here.
Otherwise, she might have been hunted down.
And Riya chose not to take the special magic cores in City B yet.