Malefic

An archaic term applied to planets and aspects whose influence was thought to be negative or destructive. Traditionally, Saturn is the Greater Malefic: Mars, the Lesser Malefic. Uranus, Neptune and Pluto were also classed as malefics. The square, opposition and other disharmonious aspects were once considered malefic aspects.

Which are the malefic planets?

The traditional malefic planets in astrology are Mars and Saturn. For practical purposes, Mars, Saturn, Uranus, and Pluto can be considered malefics. Some add Neptune to this list because Neptune can cause confusion, delusion, and dissipation.

Mercury is rather neutral.