A mysterious black notebook that can kill anyone as long as the user knows both the target's name and face.

1.- The human whose name is written in this note shall die.
2.- This note will not take effect unless the writer has the person's face in their mind when writing his/her name. 
3.- If the cause of death is written within the next 40 seconds of writing the person's name, it will happen.
4.- If the cause of death is not specified, the person will simply die of a heart attack.