Tabs (Creators of)
Who invented the stat tabs? That guy in Zeal?
A man in Zeal declares that he is working on Magic Tabs. It is somewhat logical that these enhancement tabs and others could have been scattered through time if some were present at the Ocean Palace. Still, this relies on time travel not directly seen. Another explanation is that tabs exist naturally, sort of like power crystals or diamonds. Under this idea, Zeal is attributed as finding a way to synthesize them, while in other eras they have grown naturally.
Thanks to Radical_Dreamer
From: Common Questions