"Quests of Yore" is a historically-accurate fantasy-adventure role-playing game played by Barley Lightfoot with almost religious passion due to his love of fantasy and ancient history. He keeps the game's dungeon master manual with him at all times and brings it along on the adventure.
It comes in handy during his and Ian's quest to find a Phoenix Gem as Barley has Ian practice some of the spells in "Quests of Yore" to prepare to properly cast the Visitation Spell in order to fully restore their father, Wilden Lightfoot.
Besides spells, "Quests of Yore" includes information on various mystical creatures and beings, ancient relics and artifacts, weapons, historical figures, as well as RPG stats and additional notes regarding how to properly cast the spells.
An annotated version of Barley's copy was released as a tie-in book for the film. Additionally, a fully playable board game, "Quests of Yore: Barley Edition", is set for release in the fall of 2020.
In the annotated version of Quests of Yore, it contained information about more spells than just the ones mentioned in the movie.