GURPS: Sorcery Spells with Multiplicative Modifiers
Previously, I calculated the point costs of the abilities in Psionic Powers. Today’s post does the same for Thaumatology: Sorcery. As with the Psionic Powers version, I only recalculated the costs and made no other changes, and I left certain leveled abilities unrounded. I also used the Psionic Powers version of calculating the cost of Innate Attacks with partial dice because it is easier. That may also introduce a slight difference in cost if Sorcery doesn’t do it too.
Air Spells
Air Jet
Additive: 6/level
Multiplicative: 3.2375/level
No-Smell
Additive: 63
Multiplicative: 52
Animal Spells
Animal Control
Additive: 10
Multiplicative: same
Repel Animals
Additive: 47 + 5/additional level
Multiplicative: 43.35 + 4.25/additional level
Body Control
Haircut
Additive: 11
Multiplicative: 3
Note: Under Additive Modifiers, Haircut would be a candidate for hardcore improvisation. With Multiplicative Modifiers, it is a good cost for normal improvisation. In neither case would a PC normally take it as a known spell.
Tanglefoot
Additive: 30
Multiplicative: 8
Communication and Empathy
Gift of Tongues
Additive: 28
Multiplicative: 26
Sense Life
Additive: 26 or 56
Multiplicative: 26 or 51
Earth
Flesh to Stone
Additive: 61
Multiplicative: 40
Walk Through Earth
Additive: 56 or 72
Multiplicative: 49 or 61
Note: This conversion was tedious since it required calculating Affliction, Walk Through Earth and Improved Walk Through Earth.
Enchantment
Enchant
Additive: 37
Multiplicative: 8
Note: You can take off the 1/day for the same cost. You can even remove the character point cost for 38 points! GMs should think twice before changing this too much.
Penetrating Weapon
Additive: 44 + 16/additional level
Multiplicative: 28.223 + 7.04/additional level
Notes: Imbuement based Weapon Buff advantages cost 19.36, 22.8 or 29.92 + 7.04/level using Multiplicative Modifiers. The cost listed above is entirely unrounded, so actual cost would be a bit higher. Technically, the buff advantage should be calculated, rounded then applied as an enhancement to the Affliction, but that is too much effort. 29 + 8/additional level is easier.
Fire
Ignite Fire
Additive: 1 or 4
Multiplicative: 1 or 2
Shape Fire
Additive: 19/level
Multiplicative: 15.4/level
Gate
Planar Visit
Additive: 30 or 50
Multiplicative: 22 or 44
The basic version hits the -80% limitation limit exactly while the improved version drops the limitation to -60%.
Suspend Time
Additive: 141 + 5/additional level
Multiplicative: 107.625 + 3.75/level
Note: Suspend Time is a great candidate for additional limitations.
Healing
Minor Healing
Additive: 32
Multiplicative: 18
Relieve Madness
Additive: 10
Multiplicative: no change
Illusion and Creation
Complex Illusion
Additive: 42 + 12.5/additional level
Multiplicative: 38.25 + 10.625/additional level
Create object
Additive: 56 + 4/additional level
Multiplicative: 41.6 + 1.6/additional level
Knowledge
Detect Magic
Additive: 7
Multiplicative: no change
Divination
Additive: 48 or 98
Multiplicative: 20 or 35
Note: The -70% limitations combined with the improved version having an enhancement explains the cost difference.
Light and Darkness
Light
Additive: 11 + 4/additional level
Multiplicative: 8 + 2/additional level
Sunbolt
Additive: 4/level
Multiplicative: no change
Making and Breaking
Disintegrate
Additive: 47
Multiplicative: 38
Inspired Creation
Additive: 30
Multiplicative: 27
Note: Inspired Creation’s buff advantage has no enhancements, so this calculation was relatively simple.
Meta
Dispel Magic
Additive: 60 + 25/additional level
Multiplicative: 24.375 + 6.25/additional level
Remove Curse
Additive: 65
Multiplicative: 21
Scryguard
Additive: 68
Multiplicative: 57
Mind Control
Lesser Geas
Additive: 54
Multiplicative: 48
Note: This one has a built in Limited Enhancement! These would be more common for abilities designed for use with Multiplicative Modifiers to limit abilities while avoiding the -80% limitation cap.
Terror
Additive: 45 + 15/additional level
Multiplicative: 42.075 + 14.025/additional level
Movement
Grease
Additive: 45 + 15/additional level
Multiplicative: 30 + 6/additional level
Note: This is quite a bit less costly. The extra levels do exceed the -80% cap slightly.
Locksmith
Additive: 10
Multiplicative: no change
Necromantic
Steal Vitality
Additive: 19 + 3/additional level
Multiplicative: no change
Turn Zombie
Additive: 47 + 7.5/additional level
Multiplicative: 7.875 + 10 + 1.25/additional level + 1/additional level
Plant
Blight
Additive: 44 + 5/additional level
Multiplicative: 22.275 + 2.25/additional level
Body of Wood
Additive: 98
Multiplicative: 85
Note: The Body of Wood meta-trait doesn’t change with Multiplicative Modifiers.
Protection and Warning
Magelock
Additive: 25 + 15/additional level
Multiplicative: 7 + 3/additional level
Notes: This one exceeds the -80% limitation limit. The added DR has a limitation but no enhancement, so its cost doesn’t change.
Reverse Missiles
Additive: 75 + 63/additional level
Multiplicative: 51.425 + 39.95/additional level
Note: This cost is decreased significantly. The -40% on the Reverse Missiles advantage is significant.
Sound
Delayed Message
Additive: 38
Multiplicative: 34
Thunderclap
Additive: 36 + 5/additional level
Multiplicative: 25 + 3/additional level
Technology
Awaken Computer
Additive: 45/level
Multiplicative: 40.5/level
Preserve Fuel
Additive: 45 + 5/additional level
Multiplicative: 22.725 + 2.25/additional level
Water
Icy Weapon
Additive: 14
Multiplicative: 12
Note: Unlike the Imbuement based Weapon Buffs, this one has no enhancements in the buff advantage (besides the +0% one that doesn’t change cost).
Whirlpool
Additive: 6/level
Multiplicative: 2.8/level
Weather
Cool
Additive: 7 + 5/additional level, 14 + 10/additional level, 21 + 15/additional level, 28 + 20/additional level or 35 + 25/additional level
Multiplicative: 4.725 + 1.75/additional level, 9.45 + 3.5/additional level, 14.175 + 5.25/additional level, 18.9 + 7/additional level or 23.625 + 8.75/additional level
Notes: This one was obviously one of the more tedious conversions. It is significantly less costly and does exceed the -80% limitation cap.
Predict Weather
Additive: 13 or 25
Multiplicative: 8 or 11
Multiplicative Sorcerous Empowerment
Sorcerous Empowerment is its own advantage, but what would its cost be if designed using Multiplicative Modifiers? This is more for fun than a recommendation. See the Under the Hood box on Thaumatology: Sorcery p. 5 to see how this is done.
Multiplicative Sorcerous Empowerment: 17.6 + 8.8/additional level
This isn’t much of a difference. I suggest sticking to the pentaphilic version. It would make regular Improvisation less costly, but Known Spells and Hardcore Improvisation both rely on total cost.
Final Thoughts
These calculations were much simpler than the Psionic Powers ones although there may be a few errors. The most complicated part was remembering to use the Multiplicative Modifiers for the advantage bestowed by the buffs before calculating Affliction’s cost.
Multiplicative Modifiers has the potential to incentivize designing spells with more restrictive rituals such as Requires Gestures, Requires Magic Words, Requires Material Component, etc. or limitations meant to make Sorcery act more like Magic as Skills magic such as Requires (Attribute) Roll, Short-Range, etc. Some existing spells could benefit from those limitations, but many already hit the -80% limitation cap.
Multiplicative Modifier Sorcery would benefit from spells designed with said modifiers in mind.
Some abilities may be designed differently if intended for use with Multiplicative Modifiers, but these worked fairly well. I will leave converting Enraged Eggplant’s collection to someone else.