Brahmajala Sutta says:
21. “Or he might say: ‘Whereas some recluses and brahmins, while living on the food offered by the faithful, earn their living by a wrong means of livelihood, by such debased arts as:[4] prophesying long life, prosperity etc., or the reverse, from the marks on a person’s limbs, hands, feet etc; divining by means of omens and signs; making auguries on the basis of thunderbolts and celestial portents; interpreting ominous dreams; telling fortunes from marks on the body; making auguries from the marks on cloth gnawed by mice; offering fire oblations; offering oblations from a ladle; offering oblations of husks, rice powder, rice grains, ghee, and oil to the gods; offering oblations from the mouth; offering blood-sacrifices to the gods; making predictions based on the fingertips; determining whether the site for a proposed house or garden is propitious or not; making predictions for officers of state; the knowledge of charms to lay demons in a cemetery; the knowledge of charms to cure one possessed by ghosts; the knowledge of charms to be pronounced by one living in an earthen house; the snake craft (for curing snake bites and charming snakes); the poison craft (for neutralizing or making poison); the scorpion craft and rat craft (for curing scorpion stings and rat bites, respectively); the bird craft and crow craft (for understanding the cries of birds and crows); foretelling the number of years that a man has to live; the knowledge of charms to give protection from arrows; reciting charms to understand the language of animals — the recluse Gotama abstains from such wrong means of livelihood, from such debased arts.’
These crafts are classified as wrong livelihood simply because they are not in-line with the goal. Messing around with these deviant practices will only bring more suffering.