Shroud the Stench of the Pit as an ability?

Games Discussion Ars Magica
4

So something like this?

Shroud the Stench of the Pit
Init equal to (Qik-2), MuVi 15, Shroud the infernal taint of the users magic up to 6th magnitude. (Personal Power: Two Mastery points spent to reduce might point cost to zero, Constant effect)

Or this?

Shroud the Stench of the Pit
Init equal to (Qik-2), MuVi 35, Shroud the infernal taint of the users magic up to 14th magnitude. (Greater Power: Three Mastery points spent to reduce might point cost to zero, Constant effect)