Once a person arrived in the underworld after death, he had to defend his deeds before a tribunal of gods with Osiris as the chairman. In the presence of Thoth and Anubis, the heart of the deceased was weighed in a scale against Maat, the goddess of truth. If the judgement turned out to be negative, despite all precautions such as a negative confession or an adjuration to the heart not to testify against the deceased, then he fell victim to an animal standing guard by the weighing scales, called Ammut. This name means 'she who swallows the dead'. In later times in particular, it was believed that instead of swallowing the deceased or his heart, Ammut would punish him with a knife; other versions turn the animal into a fire-spitting being. Ammut is often depicted in the vignette accompanying the relevant text from the Book of the Dead (Spell 125). In some papyri, a notation explains that she is a composite being with the head of a crocodile, the body of a lion and the back end of a hippopotamus, and this is how most vignettes depict her.