6th level (1 slot): disintegrate, globe of invulnerability
7th level (1 slot): finger of death, plane shift
8th level (1 slot): dominate monster, power word stun
9th level (1 slot): power word kill
The lich has advantage on saving throws against any effect that turns undead.
Paralyzing Touch.Melee Spell Attack: +12 to hit, reach 5 ft., one creature. Hit: 10 (3d6) cold damage. The target must succeed on a DC 18 Constitution saving throw or be paralyzed for 1 minute. The target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.
The creature can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. The creature regains spent legendary actions at the start of its turn.
The lich casts a cantrip.
Paralyzing Touch (Costs 2 Actions).
The lich uses its Paralyzing Touch.
Frightening Gaze (Costs 2 Actions).
The lich fixes its gaze on one creature it can see within 10 feet of it. The target must succeed on a DC 18 Wisdom saving throw against this magic or become frightened for 1 minute. The frightened target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a target’s saving throw is successful or the effect ends for it, the target is immune to the lich’s gaze for the next 24 hours.
Disrupt Life (Costs 3 Actions).
Each living creature within 20 feet of the lich must make a DC 18 Constitution saving throw against this magic, taking 21 (6d6) necrotic damage on a failed save, or half as much damage on a successful one.
Source:Pathfinder Roleplaying Game Bestiary.
Few creatures are more feared than the lich. The pinnacle of necromantic art, the lich is a spellcaster who has chosen to shed his life as a method to cheat death by becoming undead. While many who reach such heights of power stop at nothing to achieve immortality, the idea of becoming a lich is abhorrent to most creatures. The process involves the extraction of the spellcaster’s life-force and its imprisonment in a specially prepared phylactery—the spellcaster gives up life, but in trapping life he also traps his death, and as long as his phylactery remains intact he can continue on in his research and work without fear of the passage of time.
The quest to become a lich is a lengthy one. While construction of the magical phylactery to contain the spellcaster’s soul is a critical component, a prospective lich must also learn the secrets of transferring his soul into the receptacle and of preparing his body for the transformation into undeath, neither of which are simple tasks. Further complicating the ritual is the fact that no two bodies or souls are exactly alike—a ritual that works for one spellcaster might simply kill another or drive him insane. The exact methods for each spellcaster’s transformation are left to the GM’s discretion, but should involve expenditures of hundreds of thousands of gold pieces, numerous deadly adventures, and a large number of difficult skill checks over the course of months, years, or decades.