Today is "at some point".
What I think is the easiest approach is to actually not write up my own Illusionist spell list or tell people to track one down, but instead go the "Cleric Without Spells" approach, which I kind of like for any class that bases its powers on assistance from elsewhere, whether it be spirits, animal helpers, or in this case the victim's own mind. To avoid some confusion, I'll call this class the Mesmerist.
Concept: Mandrake the Magician, The Shadow, Morgan La Fay, and other characters who cloud men's minds.
XP/HD: As pre-Greyhawk Magic-User. Prime ability (for purposes of experience point bonus) is the lowest of Int, Dex, or Charisma.
Spells: None by default. Can research M-U spells that affect the mind, including the illusion spells (of course,) but spells known can't be "memorized", only written as scrolls. Mesmerist scrolls require 100 gp worth of belladona, opium or other drug per spell level, plus ink from an octopus, squid, or equivalent with 1 HD/spell level.
Mesmerist scrolls are not like M-U scrolls, but act more like a cursed scroll: the reader of the scroll is entranced by hypnotic diagrams that create an illusion that persists until the reader can no longer see the contents of the scroll. Knocking the victim unconscious, snatching the scroll out of his hands and burning it, or just plunging the room into total darkness will all work.
Other Abilities: Create illusions through mesmerism as a Cleric would Turn Undead. The target's HD or the spell level of the equivalent illusion (Phantasmal Forces = 2, Hallucinatory Terrain = 4,) whichever is higher, is used in place of the undead's HD. There is no equivalent to automatic turning or destruction. Success means the mesmerist has planted a vision in the victim's mind. It lasts up to ten minutes, but can be reinforced with a second roll.
Mesmerist illusions require three things:
- Eye contact (both mesmerist and victim must be able to see.) Governed by Charisma.
- Hypnotic gestures (mesmerist's hands must be visible.) Governed by Dexterity.
- Murmuring subtle commands (mesmerist must be able to speak, and victim must be able to hear.) Governed by Intelligence.
If the mesmerist's lowest ability score is higher than both the Intelligence and Wisdom of the victim, the mesmerism roll is at +1. For each score that is below the victim's scores, the roll is at -1. Multiple victims can be mesmerized simultaneously with a single roll, but calculated the modifiers separately.
Obviously, targets of mesmerism must have a living mind and at least animal intelligence. Golems, robots, and mindless undead are unaffected.