My Notes on GURPS Magic Enchantment

I've made a few rulings on enchantment over the years, and this is a good place to share them.  I use the standard magic system's enchantment rules in large part, but with my own assumptions and tweaks like I'm sure every GURPS GM has.

Overall Goals and Problems

My primary worldbuilding goal was to have enchantment be a one-man process of artistry as opposed to a factory type arrangement with large circles of enchanters, the standard assumption presented in GURPS Magic.   This presents a few challenges:

1. As written, Slow-and-Sure enchantment only allows you to put 1 energy per enchanter per day in, so even simple items would take years;
2. Quick-and-Dirty enchantment rapidly becomes non-economical unless you have multiple Enchanters sharing the load; 
3. if the supply of Enchanters is limited the PCs are going to be behind a big queue of Dukes, Kings, Archbishops, and the like so any enchantments they paid for would be even more years in coming.

My primary gameplay goal was to have PCs be able to commission enchantments and get their stuff in a reasonable timeframe, say six months to a year or so.  I also wanted PCs to be able to enchant lesser items, especially Scrolls and Powerstones, on their own.  In addition, I wanted to rationalize the price of enchanted items, as I've never cared for the sliding scale of prices between Quick-and-Dirty and Slow-and-Sure, preferring a flat rate for either.

My Solutions

I came up with a few solutions and some changes for flavor, and as stuff I find useful has come out for GURPS over the last few years I've added to the list.

#1: Removed the Scroll spell

I changed the way scrolls are prepared.  I've never found the Scroll spell to be useful or necessary, so I dropped it.  Scrolls are still enchanted items, but you don't need a separate Scroll spell, or Enchant, or any prerequisites other than knowledge of (i.e., 1 point in) the spell to be scribed and Magery (or Power Investiture for a clerical Scroll.)  You can add 2xMagery energy per day for an Uncharged Scroll, Magery per day for a Charged Scrolll, 1/2xMagery per day for a Universal Scroll, or 1/4xMagery per day for a Charged, Universal Scroll (keeping track of fractional points until the scroll is completed).  I'm using the terms from Dungeon Fantasy, but I've been treating the standard Scroll as Charged for years as my players have long viewed a Scroll that doesn't provide any energy to be useless.  Best use of a Scroll over the years: creating a 100 hex area of Suspend Mana over an evil spellcaster's sanctuary.

A Scroll has to be scribed at a minimum effective skill of 15 to be activated, and you can use Thaumatology and Symbol Drawing (Scrollmaking) as Complementary Skills to increase your effective skill as well as trading energy for skill as in Ceremonial Magic.  Scribing the scroll requires a roll against the spell when you're done as well as any complementary skills.

#2: Made Slow-and-Sure and Quick-and-Dirty Mutually Exclusive

An Enchantment can either be Slow-and-Sure or Quick-and-Dirty, but not both (with one exception and at this point a few workarounds).  The Staff spell or Powerstones and similar items are Q&D, while other enchantments are S&S. Weapon Enchantments cast on ammunition can be either.  If you take the 1/10 energy cost on appropriate ammo enchantments, you cast it Q&D but it's strictly one-shot, the Enchantment fading after it's used.  If you cast it at full cost, it's S&S and permanent (on a very fragile item, hope you added Shatterproof!)  I also broadened the list of spells that get the 1/10 ammo reduction.  After some back of the envelope calculations and a liberal amount of BSing, I decided Q&D enchantment costs $1/point, while S&S costs $20/point.

#3: Assume Professional Enchanters Put 10 Energy a Day Into Slow-and-Sure Items

I assume that there are enchanted tools, Advantages or Perks, and maybe even Techniques that PCs don't normally take that allow a professional enchanter to put 10 energy into an Enchantment a day while performing Slow-and-Sure enchantment.  PCs can put energy equal to their Magery a day in the field for S&S enchantment.  I had a simple goal here: my gut instinct was that a Sword enchanted with +1 Accuracy and +1 Puissance or a wand of Fireball should take at most a month or two to enchant.  At 10 energy a day, assuming no breaks, that's 50 or 60 days.

#4: Raw Magic to the Rescue

I added the Raw Magic rules from Thaumatology (page 227) when that book came out.  One-shot sources of Raw Magic have been excellent additions to my Random Encounter Tables.  Raw Mana can be used for any of the listed uses in the book.  In addition, you can burn a point for +3 to Alchemy when creating an elixir or +3 to any rolls required to create a new spell, and the last option has by far been the most popular use in my campaigns.

Note that when you're enchanting an item using Raw Mana, you always use Quick-and-Dirty enchantment (one of the workarounds to #2 above.)

#5: A New Addition: Magical Essences

I'm also using the rules on Magical Essences from Pyramid 3-66, "The Material Difference."  This method also uses the Q&D times like Raw Mana.  I'll post more on this one later as it deserves it's own post.

Bibliography

GURPS Dungeon Fantasy 4: Sages by Sean Punch
GURPS Fantasy by William H. Stoddard

GURPS Magic by Steve Jackson, S. John Ross, and Daniel U. Thibault

GURPS Thaumatology by Phil Masters

Pyramid 3-66: The Laws of Magic, "The Material Difference" by Sean Punch