change to Rules/HouseRules on ArtibusWiki

http://ilanin.livejournal.com/
Sat, 25 Nov 2017 01:21:37 +0000

Changed pages: Rules/HouseRules
Changed by: ilanin [livejournal.com]
Commit type: web
Date: late Friday night 11/25/17

diff --git a/Rules/HouseRules.mdwn b/Rules/HouseRules.mdwn
index c3e2f59..e2c29c9 100644
--- a/Rules/HouseRules.mdwn
+++ b/Rules/HouseRules.mdwn
@@ -146,6 +146,57 @@ The maximum size of a group for learning Hermetic Arts is two.
 Hermetic Arts can be group studied from vis, however this requires a
 quantity of vis for each maga.

+## Metamagic
+
+The Metamagic Rules in *Ars Magica 5th Edition* make it almost impossible to do any interesting metamagic even if you're the archest of magi, due to the requirements for fast casting, voice range and sundry other problems. We have accordingly rewritten them to make metamagic more feasible.
+
+### Restrictions
+
+Metamagic spells must be cast on hermetic magic; otherwise the magus is insufficiently experienced with the magic to edit it. The form and technique of the spell being cast must be known, and the spell must conform to the following set of form restrictions:
+
+1) Elemental (Auram, Aquam, Ignem, Terram)
+2) Intangible (Imaginem, Mentem, Vim)
+3) Living (Corpus, Animal, Herbam)
+
+### Ranges
+
+Touch range suffices to metamagic a spell you are casting yourself, or one created by a device you are holding. Otherwise you need to use voice range; it is not possible to use sight range unless you have previously cast an Intellego Vim spell to enable you to see magic.
+
+### Durations
+
+Usually, a metamagic spell is used to affect a spell as it is being cast, and therefore has a momentary duration since that is the time period it takes to cast most spells. However, to affect ceremonially cast spontaneous or ritual magic longer duration spells are needed. Currently, Hermetic metamagicians are unable to affect spells after they have been cast, though this is widely believed to result from a flaw in Bonisagus' theory rather than a limit of magic.
+
+### Targets
+
+In terms of strict hermetic theory, almost all metamagic is actually cast with a Part target, since part of a spell is being altered. However, metamagicians normally refer to targets (to a theoretican, these would be size modifiers) relating to the magnitude of spell being affected:
+
+* Cantrip: affect spells of 5th level or less
+* Spont: affect spells of 25th level or less
+* Formulaic: affect spells of 50th level or less
+* Ritual: affect spells of 75th level or less
+* Epic: affect spells of 100th level or less
+
+It is possible to use a Room, Structure or Boundary target spell to set up a metamagical field which will alter any spells (of the right Technique and Form and not of too high a level) cast in a region. These spells are one, two or three magnitudes higher than the equivalent standard spell, and must be cast using voice range.
+
+### Guidelines
+
+#### Creo Vim
+
+* CrVi X: Increase base penetration by X - one magnitude.
+* CrVi 10: increase range, duration or target by one level (subject to usual restrictions on what can be accomplished without Ritual magic).
+* CrVi 15: increase range, duration or target by two levels
+* CrVi 20: increase any two of range, duration or target by one level
+* CrVi 30: increase any two of range, duration or target by two levels
+* CrVi 40: increase all of range, duration and target by one level
+
+#### Muto Vim
+
+* MuVi 3: make a superficial change to a spell (something that would be within the ordinary variation of outcomes from different wizards casting the same spell)
+* MuVi 5: make a minor change to a spell (something that comes within the orbit of the guideline used; ie turn a target into a cow instead of a horse)
+* MuVi 10: make a significant change to a spell, retaining range, duration and target.
+* MuVi 20: make a major change to a spell, retaining only technique, form and magnitude
+* MuVi 30: make a total change to a spell, retaining only magnitude
+
 # Experience
 ## Adventure