How can I build a spell or invested device to allow my Magus to astrally project?

Question

I have been trying to work out how to build a spell, or invested device, to allow my Ars Magica Magus to astrally project, but been finding it difficult.

As a Mentem specialist, and I would like them to be able to un-tether their mind from their body so that it may venture forth. As a group, we already have access to scrying and teleportation spells, plus opening the intangible tunnel etc. but I wanted a more flexible way to scout without the need for arcane connections.

What I want my spell to achieve is to allow my magus to:

• Move their mind, based on the range of the spell
• Cast spells where their mind is located
• Perceive their surroundings (most likely just minds, without casting spells to perceive other things)
• Be protected by their Parma Magicka

Based on teleport being Rego Corpus, I thought the best method might be Rego Mentem, but looking through the guidelines, that's all about controlling other peoples minds rather than moving minds (other than Exchange...). Muto Mentem is similar, and I can't find anything in the Animal guidelines which might help either.

I suspect the key factor may be the casting spells, so it might be best to build this as a General level ReMe(Vi) or ReVi(Me) spell, where the level of spell will determine the level of spells able to be cast at range, but I'm having difficulty trying to work out what the +/- factor would be.

The other problem with basing it on Opening the Intangible Tunnel is that it feels like the mind is staying where it is, but it's just moving the end if the tunnel to affect/perceive the world. I actually want the story possibility of an out of body experience. Maybe the answer is to separate the two, and have one spell to move the mind, and then use the knowledge gained to provide the arcane connection to target the Opening the Intangible Tunnel or Summoning the Distant Image etc.

As always, references from the rules as written, and or house rules based on actual experience would be appreciated.

^{Note: We are playing 4th edition, but with house rules on spell penetration based on those in 5th edition.}

Answer 1

In my game, the first part of this would be simple. Humans have spirits, ReMe could potentially be used to "release" a Magus' spirit, allowing it to wander about exactly as you describe. The soul (which is immune to Hermetic magic) would stay with the body, which would be helpless for the duration. A spirit "naturally" does much of what you want, so this covers most of it.

The more complicated issue becomes spell casting. I would probably allow a Vim requisite to give the spirit access to spellcasting...allowing the Magus' Gift to "tag along". Your idea to cap the allowed casting spell levels at the level of the Vim effect seems reasonable...I think a 1 for 1 level of Vim is sufficient here (no accounting for duration as is done with many Vim effects). So a level 30 Vim effect would allow up to level 30 spells to be cast.

Allowing the spirit to have Parma access I would consider to be reasonable with no further effect. Spirits have a Might score and using the Magus' Parma to determine this number is reasonable to me. If your group disagrees, another option might be to allow yet another Vim effect which would grant the Spirit a Might score to replace the lost Parma. Even in this case, I think the Spirit should at minimum have a Might equal to the caster's Mentam score. If I did allow free access to Parma in this form, I might not allow a spirit to work the Parma ritual itself...meaning that if you were in spirit form when it dropped you would be stuck...and you would be unable to suppress it to allow a desirable spell in.

Keep in mind that each of these 2 (or 3) effects would require a separate spell...or a single spell at increased level with Reqs.

Just some things off the top of my head...if I put more thought into it (seems likely...thanks!) I might refine some of this, but hopefully it gives you something new to think about.