@JeremyECrawford What happens when a duplicate of the invoke duplicity domain is attacked?
— smbbama (@ButlersBestDeal) September 12, 2016
The illusion created by Invoke Duplicity is invulnerable to damage. A weapon passes right through it! #DnD https://t.co/TjEOoAEAxy
— Jeremy Crawford (@JeremyECrawford) September 12, 2016
Does this mean the attack automatically hits the illusion? Additionally, is there some sort of save for the creature to determine that its an illusion once the attack passes through the illusion?