Some of the spell localization is broken, causing the names of e.g. Ancient Scrolls to display strangely.
(Note: this occured on a custom modpack. I will attempt to check later whether this is a more general problem.)
gamma-delta commented
what
oh god that's a dumb error hold on
gamma-delta commented
For anyone coming here later, run /hexcasting recalcPatterns to fix it, new scrolls should generate properly