@JeremyECrawford @mikemearls Does adamantine armor nullify the effects of magical weapons when you roll a 20
— Younes Kamal Eddine (@Younes_KE) March 22, 2016
Adamantine armor turns a critical hit into a normal hit, yet if you rolled a 20, you still rolled a 20. #DnD https://t.co/6YCYoJShsO
— Jeremy Crawford (@JeremyECrawford) March 22, 2016