This crown appears as one of a number of things.
A sturdy iron circlet set with black opals.
A shining silver diadem with three shimmering diamonds.
A gleaming gold crown inlaid with rubies.
A brushed steel band with four saphires.
Its appearance is as that it thinks will be most pleasing to the character it wishes to be on. Once anyone places it on their head, the crown becomes invisible to all but the wearer and cannot be removed. It also becomes insubstantial in that it will not affect the wearer putting on a helmet or hood. If inspected for magic, it may show an aura of divinaton or guidance.
Whenever the wearer has to make a command decision (which fork to take, whether to question the prisoner or beat them, etc), the crown starts to help. This help comes in the form of four voices coming from the four sides of the crown that only the wearer can hear. Law to the front, Chaos in the the back, Good on the right and Evil on the left. Each voice will pipe up and give their input on what they think the wearer should do. While the voices are speaking to the wearer, the wearer’s sense of time alters so that four voices can speak their peace, at whatever length, in one second, then if they bicker or argue, every fourth voice is another second. While the voices speak the wearer may seem unfocused or distracted and may even turn their head to listen more intently to one voice or flinch from a shouting match. This would become more pronounced after long arguments and the wearer may even start to argue out loud to the voices.
There are only two known ways to remove the crown. First the crown becomes visible and corpreal again after the wearer dies. Second, the wearer must defeat a major force that represents a voice of the crown and continue defeating these major forces untill they have defeated one for each voice. The voice whose force the wearer is going against will adamantly speak out against the wearer taking it on, but after the force is defeated, the voice becomes distant and echoing, untill all the forces have been defeated, at which point the crown becomes silent and can be removed. Major forces could be spiritual leaders, generals, nobles, etc.