@Lucky either this world already has them... or he has somehow commissioned the local smiths/glassworker/artificer to make them.
It's this sort of inconsistency that weakens the isekai genre, to be honest. But as long as the world-building provides an explanation in future chapters, I can roll with it.
It's this sort of inconsistency that weakens the isekai genre, to be honest. But as long as the world-building provides an explanation in future chapters, I can roll with it.