Attacks with Slip Touch and Drain.
The Nightwalker, also known as Pm Stalker, is an enemy in Final Fantasy VI.
They are not powerful, but attack in groups. Like many other undead type enemies, it is weak to healing and fire-elemental spells. If Celes knows Fira, Cura, or any other level two spell, it can be used to kill the group quickly in one casting.
1st Turn: Attack (66%) or Drain (33%)
2nd Turn: Attack (66%) or Sapping Touch (33%)
If attacked by "Attack": Drain (33%)