Mutation magic (or Muto) is a technique which is very powerful, but has only a small set of effects in the core rulebook. The guidelines for new spells indicate side variations and options that I found interesting enough to work up as a few sample spells. Muto covers all changes to whatever it is applied to. This can be small partial changes like changing the colour of somebodies hair, or full changes like turning into a bird or wolf.
On first thought changing into an animal is very cool, there is however the somewhat tricky limitations in Ars Magica for changing shape.
The first is that your carried gear and equipment will either make the spell harder to cast, or be left behind when you transform. This gets slightly worse when the mage returns to normal, and is missing their gear. Standing naked in open places can make a mage seem less striking. To solve this there is an common spell used by some shapeshifters to create the illusion of clothes (see Disguise of the Transformed Image, ArM p146). Bundle that with a small easy spell so mage does not feel the cold as much and they’re at least civilized.
A magus might wish to polymorph their clothing into a more suitable type, or need a special type of clothing to enact a spell. The following spell is cast on existing clothes, to give the caster a far greater range in their wardrobe. The core effect is based upon “Coat of a Hundred Colours” spells Wiki by Andrew Gronosky, which is a simple and effective idea.
Attired as Desired
Muto Animal 20 / Herbam Terram. R: Voice, D: Sun, T: Individual
Changes all the clothing of the target touched to the desires of the caster. Purpose of the spell is to allow a quick outfit change should circumstances demand, and also so that the clothing of the target to become appropriate foci for the Muto Corpus spells. It saves carrying around five different cloaks.
(Base 3, +2 Voice, +2 Sun, +1 highly complex clothing).
I created this spell so that it could be cast at some range from the target, just in case touching the target would be difficult. It could be lowered to level 10 if it only affected the caster.
Second issue is the fact that once a mage is changed into an animal, they have no hand or voice to cast spells. In game mechanics this imposes a -15 penalty to the spell casting roll. Bjornaer mages have a way around this, which is to mutate their new animal form so that it can speak as a human (See Voice for the Bjornaer, from HoH-MCp36).
A re-working of that spell is provided here, modified so that the caster can assist others who have been shape changed into Animal form.
Gift of the Master’s Voice
Muto Animal 20, R: Touch, D: Sun, T: Individual
The target’s animal form gains the facility of human speech, although still heavily tainted by aspects of the creature’s shape. This spell does not impart the knowledge of how to speak, so has little effect on non-shape-changed creatures.
(Base 5, +1 Touch, +2 Sun)
Thirdly the type of spell used to affect a target who is changed into an animal must also be designed for animals. This makes many of the other enhancing effects that human wizards have designed somewhat useless for a shape-changed Magus.
by way of example this spell is used to change the costmetic appearance of an shape changed target.
Disguise of the Chameleon
Muto Animal 10. R: Personal, D: Diameter, T: Individual
Allows the caster to change the cosmetic appearance of their current animal form for a short period (approx 2 minutes). Size is limited to affect up to size +1 creatures.
(Base: 5 change an animal in a minor way so it is no longer natural, +1 Diameter).
Now as samples the following spells change the caster into a new form of some sort. All of these spells could be increased by 5 levels (+1 magnitude) to make them range Touch, so they could affect others.
Poise of the Cat
Muto Corpus 5 / Animal. R: Personal, D: Sun, T: Individual
Grants the magus the sense of balance and poise akin to a cat, apply a +3 bonus on rolls for appropriate Athletics checks.
(Base:3, +2 Sun)
I debated if this was base level 2 or 3, but think that the physiological changes to assist balance are slightly more than changing the caster’s eyes or similar spells, so chose a level 3 base.
Senses of the Bloodhound
Muto Corpus 5 / Animal. R: Personal, D: Sun, T: Individual
Grants the magus enhanced sense of hearing and smell akin to bloodhounds, adding +3 to all appropriate perception based tests.
(Base: 2, +2 sun, +1 extra sense, req free)
The main rulebook has a higher level spell which changes the caster into a wolf. As an example of a slightly different spell – the target animal below is a lion. The difference is that the Muto spell guidelines must also consider the size of the final form, and a lion is size +2 which makes this spell slightly harder than a wolf, although the target of this spell has also been updated to Personal – which keeps the overall level the same.
Shape of Fearsome King
Muto Corpus 25/ Animal. R: Personal, D: Sun, T: Individual
Changes the magus into a Lion form.
(Base 10, +2 Sun, +1 due to extra size requirement of lion form)
Now is a standard size lion or wolf is not large enough, here is another spell designed to increase or decrease the size of an animal form while shape changed.
Unearthly Magnification of the Beasts
Muto Animal 30. R: Personal, D: Diameter, T: Individual
This spell allows for temporary growth or shrinking of the Magus’ animal form up to Size 11 or down to size -12. The spell may target any creature of up to size +4, but may only change the creatures size by up to 10 size ranks in either direction.
ie. A size a +4, may become up to size +11 or down to -6. A size -3 creature may become size -12 or up to size +7.
(Base 4 for changing creatures size in an unnatural way +/1, +1 to allow for shrinking and growing in the same effect, +1 D:Diameter, +1 mag to affect creatures of up to size +4, +3 to change up to size 11, or down to )
This is an altered form of Beast of Outlandish Size combined with Preternatural Growth and Shrinking – specifically for casting while in an animal form, due to the Personal range.
Update: The spell magnitude vs the size of creatures is not stated in any of the books, and initially I made the assumption that each +1 rank in size was +1 mag – it is not actually linked in that manner, and re-sizing is far easier. From a forum discussion on changing size:
Tellus wrote: “An elephant is size +4 (per ArM5 p. 192). Base individual is up to size +1 (ArM5 p.117). +1 for size adds about a factor 10 of mass (ArM5 p. 113) a factor 10 worth of mass is about roughly a size change of +/- 3 meaning size +4 is a size modifier of +1, maybe +2”
Lasse Rohde replied: “The rules for creature size in the bestiary section of ArM states that an increase (or decrease) of three points of Size is approximately equivalent to a factor of ten change in size. So I’d say a +1 magnitude for size, should target animals of up to size +4.
This means that all animal buff spells of the caster would need an extra magnitude. On the other hand, the spells of his enemies might not be able to target him at all!”
My read of this now is that for each +3 shift in size ranking a +1 mag is needed in a spell effect. That makes paying +4 extra magnitudes for a shape size change spell really powerful, with a huge change in creature size. The “Unearthly Magnification of the Beasts” effect was set specifically to affect creatures which are larger than Size +1 as the Magus character I designed it for already had a spell to change into a Lion (a size +2) creature. This means the spell must first affect the Lion’s form, and then alter it. In effect the magnitudes of power need to be split between targeting a creature, and then changing it. The change is a huge shift in the final size of that character’s lion form when used.
Muto is not just for shape-changing, it may also be used with a direct combat application. Here are spells that target an opponent and use Muto Corpus in some way.
Polymorph the Belligerent Rabble
Muto Corpus 30 / Animal. R: Touch, D: Diameter, T: Group
This spell changes the targets within the group into sheep for up to two minutes.
(Base 10, +1 Touch, +1 Diameter, +2 Group).
A human shifted to sheep form will have little or no defenses, and two minutes should be sufficient to dispatch the targets while they are polymorphed.
The Diminution of Man
Muto Corpus 15. R: Voice, D: Diameter, T: Individual
Reduces the target’s size to -3, that of a baby.
(Base 3, +2 Voice, +1 Diameter, +1 extra size rank down to size -3)
Targets affected will find their combative stats so greatly reduces, that they are all but neutralized.
Silence the Babbling Fool
Muto Corpus 20. R: Touch, D: Diameter, T: Part
The target of this spell has their eyes and mouth close over, as if they were born that way.
(Base 5 to change a person in a minor way so that they are unnatural, +1 Touch, +1 Diameter, +1 Part)
Lastly is a non-shape changing spell, instead is a spell that changes the text and illustrations within a document.
Disguise the Words as Written
Muto Imagonem 5. R: Touch, D: Sun, T: Individual
Allows the caster to change the contents of a letter or document, re-writing the message, changing seals, and altering signatures to create another message. The letter may also be rendered into jibberish. Useful for sending secret messages by mundane means, and also for altering official documentation
(Base 1, +1 Touch, +2 Sun, +1 very complex image and text)