Possible Clues:

• Visionary giving advice
• Tiresias, in 'Oedipus Rex'
• Future revealer
• Guide leaving town — he knows what's coming
• Future viewer?
• Pundit, aspirationally
• One with tomorrow's forecast
• Professor Trelawney in the Harry Potter books, e.g
• Medium, e.g
• "Sucker" add-on