A dragon's Frightful Presence does not state that it follows the rules of spellcasting, but does it when determining a clear path of effect? If not, I don't know how to determine if it goes through cover, goes around corners, etc. @JeremyECrawford
— Dallas N. Arrington (@DeoxyNerd) 7 maggio 2018
The text of Frightful Presence states who's targeted: each creature of the dragon's choice that's within range and aware of the dragon. Nothing else is required. #DnD https://t.co/qa9YKtGdOm
— Jeremy Crawford (@JeremyECrawford) 7 maggio 2018
What constitutes “awareness” of the dragon?
If someone in range knows a dragon is on the other side of a wall, but hasn’t actually seen or heard it, does that count as being “aware” of it?
What if they’re slightly mistaken? What if they only THINK they know where the dragon is, but it turns out to actually be somewhere else, but still within range?
What if they have no idea where the dragon is located, but they know for a fact that it must be nearby, due to various kinds of evidence?
What if they are in telepathic communication with a dragon (and are hence “aware” of it), but they don’t realize it’s actually nearby?
What if an enchantment or an illusion causes them to perceive a dragon as something else, such as a humanoid?
I know modern D&D like to rely on “natural language” for the rules, but this is one of many cases where natural language fails us, because the language used is fundamentally imprecise and self-contradictory depending on context.