Recently I've been getting into Gurps's "Standard" Magic system, for a couple of different reasons. As part of this, I've been looking hard at Magery prerequisites for spells. They're surprisingly good! The idea that some wizards can cast more powerful spells than others is just sort of natural.
But that's not how things usually end up playing: There is a strong incentive in Gurps for every Player Character wizard to have magery 3, which is the maximum. Why? because in the standard magic system skill 15 is everything, and magery is the cheapest way to boost skill. There is no choice between the ability to cast spells more reliably, cast spells more efficiently, or cast more impressive spells: the most effective way to do all three is to buy magery as high as the campaign allows, and then any specialization comes after that.
But what if we associate magical power with the amount of energy available to a mage, rather than with magical talent?
Energy-Based Magery
When using this rule, skill-boosting Magery is renamed "Magical Talent", and doesn't get used for prerequisites. "Magery" refers to a composite advantage consisting of 3 levels of Energy reserve and a perk letting you cast spells with a prerequisite of that level of magery (kind of like in RPM). Level 0 Magery doesn't change.
Analysis
This rule has some pretty big effects:
- Mages have permission to buy more Energy Reserve, as well as an increased incentive
- Bigger Spells are going to be cast more often
- Reaching Skill 15 will happen less often
- Mages will have to choose between reliability and efficiency vs. access to the best spells
- Mages will be just a little weaker
I think this is a good change in most cases, but it won't be in all cases. Ask yourself if the change fits your campaign. I'll probably be pairing this with my recovery energy tweak, to allow mages who go for power rather than skill to not miss out on that critical ability. I hope this makes your games more interesting!