green hag problem

[Huw]

In an old campaign I ran, the party were being stalked by a Type III demon (glabrezu to you young'uns) with the ability to change its size. It simply became as small as a flea and hid on a different party member each day. At the end of the day, it would bite that character to feed (one damage, but really annoying the party), then move to someone else. Took the party 2 weeks of game time to realise what was going on, during which time they realised that this demon had eavesdropped on some pretty important stuff .

 

[Dancer]

Divination.

If the sorcerer doesn't have access to some type of divination then the party should go to some npc who does. Find out a time and place where the hag will attack next and set an ambush for her.

 

[Baron Opal]

Set a trap. Put word out somehow that the party wishes to buy off her emnity with gold and magic. When she comes ambush her.

I second glitterdust as a must have spell. Not only does it foil her invisibility but there is a chance she'll be blinded.