This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
Malefic Grahas gathers four of the nine grahas of Jyotisha classified simply as malefic, without the mild qualifier carried by a fifth, the Sun: Mangala, Shani, Rahu and Ketu, two of them ordinary planets and two of them shadow points with no physical body at all.
Mangala, Mars, senapati, commander of the planetary cabinet, is karaka of energy, courage and drive, signifying younger siblings, land, muscles and blood, engineering, weapons and competition; exalted in Makara, debilitated in Karka, ruling Mesha and Vrishchika, his day Tuesday, his gemstone red coral, his Vimshottari period seven years. Shani, Saturn, is the great malefic proper, the slow and impartial judge who dispenses the fruit of karma, karaka of time, discipline, labour and renunciation; exalted in Tula, debilitated in Mesha, ruling Makara and Kumbha, his Vimshottari period nineteen years, the second longest of all nine.
Rahu and Ketu are chhaya grahas, shadow planets, the severed head and tail of the serpent Svarbhanu, marking the two points where the Moon's path crosses the ecliptic rather than any physical body, which is precisely why the atlas's own note on the word graha, seizer, defines the class by its grip on a nativity rather than by being a body at all. Rahu, always retrograde, signifies insatiable desire, ambition and sudden upheaval, magnifying whatever it contacts, with an eighteen year period; Ketu, its opposite, signifies detachment, renunciation and moksha, with a seven year period matching Mangala's.
All four are set out among the nine grahas of the Brihat Parashara Hora Shastra, and Rahu and Ketu specifically in Indian astronomy's mathematical treatment of the lunar nodes rather than as bodies.