Is all the speech of the deceased in a dream, whether it be a warning or a will, real and obligatory to implement, and is it directed by the deceased or by Allah?

Visions are of three types: righteous, which is glad tidings from Allah; a vision that causes distress, from Satan; and a vision of what one says to oneself. A righteous vision is part of prophethood, and it is either a harbinger of good or a warning. No legal ruling can be derived from it. If one sees a person they know, it could be that person, or it could be Satan impersonating them—except for seeing the Prophet, peace and blessings be upon him, with his known attributes, for that is true. However, no legal ruling is established through it. The speech heard in a truthful dream is the speech of the dreamer, not the speech of Allah.