Dagger Diabolic

This dagger is possessed by a demon that exerts its influence empathically.   If in the hands of a Good or Neutral character, it's malevolent influence comes into effect and if held for only up to 4 rounds, it will act as only a +1 dagger.  If longer than 4 rounds, the wielder must save vs magic or begin to become convinced that this dagger rightfully belongs to them and will quarrel with anyone else laying claim to it.  If the save is made, the character will be repulsed by the dagger and cast it away, not wanting to handle it again.

When worn on the body somewhere upon their person, a dagger sheath, etc.. the wielder seems to be in a foul mood, irritable and short tempered. When taken in hand, the wielder feels very aggressive and especially vicious, seeming to be looking for a fight and tending toward unusual violence and cruelty.

If kept and worn for more than 4 hours, it's full effects are felt by the wielder and their personality is affected as described. In the hands of someone who has become affected by it, it operates as a +3 dagger with a chance to do 2d4 damage on a natural 20.

In the hands of an Evil aligned character, it operates as a +3 dagger with a chance to do 2d4 damage on a natural 20 with no other influence on their personality (as they are already Evil).

Casting of the Clerical spell "Dispel Evil" will disrupt the effects of the dagger on the wielder and they will be able to see the dagger for what it really is.
If "Detect Magic" is cast upon the dagger, it will be detected.