The Heads for no Tails are very powerful shackles that were first introduced in the story of Bolgrot's birth and were a part of a few other important events. Although their appearance differs starkly in various media, their original description seems closer to what one may consider canon.
The birth of BolgrotEdit
Shortly after the creation of Xelor's Clock, in the year 10, Djaul attempted to trick the Dragon Aguabrial into laying a new Dofus, which he would then steal and use to increase his power. To achieve this, he created an Ondine, a water nymph Aguabrial was meant to fall in love with – which he did. As is common for Dragons, he laid an egg as a demonstration of his love, and Djaul waited for the egg to gain power before stealing it.
Before he was ready, however, Aguabrial's alchemist friend Ereziah Melkewel visited the Dragon and realized that something was afoot. He tricked the Ondine, and Djaul who was watching in the shadows, into thinking he would come back with a present and enchant the Dofus to increase its already impressive power. In reality, he returned with shackles that threatened the Ondine's life and forced Djaul to come out of hiding. The complete story can be read in Found Fragments VI a., but the following excerpt describes the shackles' appearance and properties:
Under the eyes of Aguabrial, the ondine and Djaul, [Ereziah] uncovers a strange sculpture: four heads stuck together with proeminent jaws. He called it 'Heads for no Tails'. He presents them the heads as a very old magic mechanism worthy of Xelor himself, a real work of goldsmith and jeweller. (...) 'Put your wrists inside the magic jaws and they'll adorn you with the most beautiful bracelets you've ever seen'. The innocent obeys. The jaws shut close onto her delicate wrists which were adorned with... handcuffs and chains! 'The particularity of these magic bracelets is that they prevent you from drawing the energy you need to survive...'
— Found Fragments VI a.
When Allister tricked Esra'Ruoy'Dnim in 512 to stop his invasion and put an end to the slavery he had subjected Amaknian citizens to, he used the Heads for no Tails ro restrain him before sending him to Astrub's prison. According to that story, the artifact has been passed down his family for generations. While Ereziah was also a Feca, it is not known whether they share the same blood or the shackles were given to Allister's family at some point.
Kerub and JorisEdit
In episode 34 of Dofus: Kerub's Bazaar, Clics Claques, Joris gets stuck in an interpretation of the Heads for no Tails that looks more like a box and completely restricts movement. A flashback shows that Kerub simply took the artifact from a Crocodyl who left it at a bar and never came back for it. Since the series takes place in 397, it would seem that the restraint had several owners between Ereziah and Allister.
In the episode, the shackles are opened by a password, but it is not revealed to the viewer as thunder always strikes while someone says the word (both in the flashback and at the time Joris is released from them).
While the password is never heard, the most common guess to it is "raconter", a shorthand for the phrase "raconter une historie", literally tranlating to "to tell a story".