Vancian vs. Moorcockian Magic

Vancian magic is the rule of the day in many old-school games, although spell points (per our own P&P) come in second, with several variations of these themes.  Both approaches have something big in common; chiefly, that characters have but a limited number of spells they can use in a given period, which is the point.

Really, the designation "Vancian" just refers to the narrative justification for why characters might not be able to cast more per day (i.e., the words fade from the magician's mind).  There are undoubtedly a great many rationalizations for why this might happen, like running out of "energy" or whatever.  

But the real idea is that spell-casters have a limited number of available spells per game day as a means of overall balance.  Spells make the impossible happen, and this power must be bounded lest these characters dominate the game.  But there's another element of old-school magic; that of magic as an IMPERSONAL force.

In these games, magic use is almost universally depicted as some pseudo-scientific manipulation of natural energies, and this is certainly more palatable to anyone still worried that role-playing somehow teaches kids to summon  demons.  But this doesn't square with how, historically, magic was thought to work.

Elric of Melnibone (P. Craig Russell)

Traditionally, magicians were thought to call and command an assortment of demons, elementals, and spirits based on the specific culture and/or religion in question.  Again, this approach may be questionable to some, especially those possessing certain religious convictions and anyone who feels this somehow detracts from the magician's personal agency, etc.

But then, Jack Vance wasn't the ONLY writer who influenced the emerging hobby.  Michael Moorcock, creator of Elric, that tortured anti-hero of Melnibone, imagined a world of ancient and powerful entities sworn to law, chaos, and, often, only to themselves, bound by pact to a people and subject to their enchantments...

In a "Moorcockian" setting, magic involves commanding various spirits, and this is also a matter of justification, subject to the following alternate magic rules:

(1) Spells are cast by commanding spirits, which means they aren't really formulas so much as powerful spoken names.

(2) When a spell is cast, there are discernible, visible effects related to the spirits being called.  These linger one round beyond the effect's stated duration before fading.

(3) Yes, even spells that otherwise conceal the caster, and this is left to the GM to work out as befits a particular effect.

(4) If spells known are NAMES, then spell slots (or points) represent the number of times per day that spirit can be reliably commanded without consequence to the character.

(5) Sorcerers might attempt to utter known names beyond this limit by rolling saving dice (against death, where applicable), with failure still indicating success, but also a loss of hit points as decided by the GM.  Perhaps 1d6+1 per spell level in D&D...

Spells that deal damage can be
re-imagined as THIS within the narrative context...

As a balance, spirits may only be summoned under specific environmental conditions.  For instance, fireball involves calling fiery elementals in the presence of a torch, etc.

By way of example, the following spells (from Pits & Perils) as presented in a Moorcockian system:

SPELL           ENVIRONMENT           NAMES ASSOCIATED
Calm            air/wind              Balaat, Muhr  
Hide            shadows/night         Kohur, Nizaria
Ruin            blood/fire            Glazrebul, Mahabdrah

Of course, characters can learn new names, and might possibly uncover MAJOR NAMES.  These correspond to demons and possess powers commensurate with the system being used.  These may be called, although doing so ALWAYS requires saving dice or expenditure of a number of spell points (or slots starting at 1st level) equal to the being's level or something similar per the GM...  

These linger for a number of rounds equal to the character's level and perform as commanded within limits.

With minimal effort, most old-school systems can adopt this Moorcockian magic system which is, after all, really just another justification for WHY magic works and why it's so limited.  But summoning spirits alters the narrative as well and opens the door to unique rules, easily implemented, that make magic challenging!