Related

Location
Castles
HP
1
Notes
Will sometimes steal your highest-tier unequipped weapon when adjacent; drops the key to a random prison cell
Killing the Jester gets you a key to one of the castle prison cells, but it also makes the Guards attack you. Whether you get the key to the Princess's cell is random, and the only way to find out is to try to open it.
The Jester will randomly decide to steal Weapons if you happen to be standing in an adjacent square, much like Bards in towns. The Weapon stolen is the best one in your inventory, though Jesters can't steal the Weapon you have equipped. (They can steal extra copies of it, however.)
The Jester will randomly decide to steal Weapons if you happen to be standing in an adjacent square, much like Bards in towns. The Weapon stolen is the best one in your inventory, though Jesters can't steal the Weapon you have equipped. (They can steal extra copies of it, however.)
Location
Castles
Notes
Will sometimes steal all of your unequipped weapons when adjacent; drops the key to a random prison cell
Killing the Jester gets you a key to one of the castle prison cells, but it also makes the Guards attack you. Whether you get the key to the Princess's cell is random. You can check your inventory to determine which key you got—you want the key to cell #2.
The Jester will randomly decide to steal your Weapons if you happen to be standing in an adjacent square, much like Bards in towns. They will steal all of your reserve Weapons, so try not to give them the chance. If possible, use a ranged Weapon to kill a Jester so you don't have to get near them.
The Jester will randomly decide to steal your Weapons if you happen to be standing in an adjacent square, much like Bards in towns. They will steal all of your reserve Weapons, so try not to give them the chance. If possible, use a ranged Weapon to kill a Jester so you don't have to get near them.

Experience
2
Jesters are weak foes and are rarely aggressive, but they can be annoying so I really can't blame you if you kill a few here and there. Interestingly, the only Jester in the game with a worthwhile hint is the one being tortured in the Castle of Lord British. (Maybe he was being tortured for not being annoying enough?)