One of my players wants to create a spell (well, an effect really, but you get the idea) to shrink a door to the point where it is small enough to put in a pouch.
This would obviously be muto herbam (assume a wooden latch). But what level would the base effect (shrink wood) be? and how much would it shrink that door by?
There are 2 ways to look at it :
The door is an inanimate object, so you could use the MuTe guidelines; and use "Object of Increased Size" as a guideline.
Or, you could use MuHe guidlines, with "Pass the Unyielding Portal" to help;
I would apply the target size rules (+1 Magnitude for a tenfold increase in volume, which equals +3 size, so a +1 magnitude for a tenfold reduction, for -3 size) as well. This would make spells to make something extremely small as difficult as those to make something extremely large. A normal door is size +1, and you want to reduce it to fit in a pouch. We'll say, to size -5.
Given that Touch range is a requirement, we'll use that as well, and Sun duration.
Base Level 3(MuHe Guidelines)/4(using MuTe guidelines)
Range : +1 Touch
Duration : +2 Sun
Target : +0 Individual
Target Size : +2 (100 fold reduction)
So... Level 20 or 25, without frequency or other modifictation.
The MuTe version would have a casting requisite of Herbam, but since it is required to make the spell work, it doesn't adjust the level any. However, adding a Te to the MuHe version requisite would add a level, Since it is not strictly nescessary for the spell to work.