I'm currently making a creature for a game and suddenly unsure of how to build it.
The power mimics one of the game Octopath traveller's main enemies. That is: a creature which if you see it, you turn to stone until the time the creature dies.
Obviously the base is 25 in MuCo(Te) (requisite for animal added, no reason why not, additional +1 magnitude). Spectacle target seems adequate (you see it, it affects you). Personal range okay.
But then it's the duration which I'm stuck with.
This power has, indeed, two:
the fact that the power for the creature is constant;
the fact that once you are affected, you cannot turn back unless the creature dies. It rings to me as a "until" duration", which is +4 magnitude iirc.
But if I put the until duration, I do not really capture the fact that this power is constantly active on the creature (and it's might point consumption would become troublesome)
If I use a sun/constant duration, I do not really capture the fact that you can only turn back when the creature dies, nor does it seem right to have multiple "target" be affected in that way.
As it's a magical power, you have room to adjust it as a "non-hermetic effect" and can play around.
If a Hermetic magus tried to do it with Sensory magic, the rule on HoH:TL p27 of "The effects on all targets ceases with the spells expiry, no matter how long they have been affected" would apply so they would need the Until duration.
"Until the creature dies" means the creature has the effect in operation until it dies (so always on) and also that targets are affected until it dies. This is probably the simplest solution.
I would agree for simplicity in matching up to other rules. Also, Until isn't normally distillable. Lower the Might cost if you need to preserve Might Pool.
Treading the Ashen Path might be a suitable reference.
That spell's design is essentially to continually recast its basic effect a few paces wide as the magus walks.
So this spell can be a Momentary, Sensory Until spell that acts similarly for the spell's stated Duration. Add magnitudes for weirdness, similar to TtAP.
Formulaic spells, after all, can bend the T/D/R a bit.
If you don't mind using faerie guidelines, I think it could work as:
Range: Sight/Eye (Depending on what you mean), Duration: Faerie (As long as it's alive and in the normal world, the duration extends) Target: Individual (A size 0-ish person)
The only problem is that it would need to pay for each "cast" of the power out of might points, and it would "go off" at it's initiative.
You could buy down the might point cost by taking either mastery or intricacy points to reduce the cost. So it could be a free power.