Sorcery: Gem Magic

Sorcery: Gem Magic

My favorite worked example in GURPS Thaumatology is the gem injection magic (p. T239). Gems often are said to have supernatural powers, and this system lets characters inject addicting gem dust to cast spells. Let us try to adapt this to Sorcery.

First, the gems are incompatible with each other. This is represented by the Accessibility, One college at a time, -10% limitation applied to Sorcerous Empowerment. An addict has access to a single college at a time, depending on the gem used. The only way to switch colleges is to take a new shot while the previous effect is still active, which is a traumatic experience: the user must make a HT-3 roll or fall unconscious for 3d minutes, during which time his new abilities may expire. Even if he succeeds, he’s mentally stunned (p. B420).

Second, gem injection is addicting. This is represented by the Required Disadvantage, Addiction, -20% limitation applied to Sorcerous Empowerment. Gem injection is an Addiction. It’s impossible to use the magic if one isn’t hooked – the process involves succumbing totally to the rush. The habit is very expensive, highly addictive, and causes psychological dependency, and is illegal in most places. Addiction (Gem Injections) costs -25 points. The limitation value is set at -20% for simplicity, however, because this is technically legal in some places, where the local laws have not caught up.

Very expensive Addictions cost more than 0.5% of starting Wealth per dose. I'd suggest putting a gem dest injection at 4%, making a dose cost $40 at TL3. Gem injections require gem, water, syringe, five minutes of work, and a successful Ritual Magic (Gem Magic) roll to craft. If you find a gem during your adventures, you can find its cost using the formula from GURPS Dungeon Fantasy 8 - Treasure Tables, p. 19 and determine how many doses can be crafter out of this particular gemstone.

Third, we should apply the Trigger, -30% limitation to Sorcerous Empowerment. The addict can work magic for 2dx3 minutes after the injection.

When rolling a critical failure on a casting roll, use the “Reality Warping” Table (GURPS Thaumatology, p. 259) – but on an 18, the caster suffers a heart attack (p. B429) instead of the usual results.

All spells are unreliable due to the nature of this type of magic. Apply Unreliable, 14, -10% limitation to all spells. This is included in the Gem Sorcery power modifier.

Learned spells require an additional limitation - Accessibility, Only after injecting an appropriate gem, -10%, because even if Sorcerous Empowerment is not disabled, the scope limit of the injected gem still applied. This is not included in the Gem Sorcery power modifier.

After all adjustments, Sorcerous Empowerment (Gem) costs 8 points for level 1 + 4 points/additional level, using the Gem Sorcery, -25% power modifier for spells. For specific gems and the powers they possess consult GURPS Thaumatology, pg. 240-241.