Circle warding level

[orneen (MONTBILLIARD)]

In the core rulebook, page 120, creating a guard circle, it is stated that the creature's Power level must be greater than the spell level to overcome the protection.

When we speak of level, do we mean the final level of the spell or the base effect?

[Red-Shadow-Claws (Itzhak Even)]

The spell's level must be equal or higher than the Might of the creature to be warded against, but do note that the spell also needs to Penetrate the MR, so essentially, your Casting Total should be Twice their Might.

[silveroak]

Fundamentally it is calculated from base effect. You do not protect against more powerful beings by covering a larger area.

[raccoonmask]

If you do a dissection of the numbers, the Wards vs Mighty creatures are calculated at Touch + Ring + Circle.

Actually, now that I'm examining it, it's stated in another part of the Spells chapter.

@Ars Magica Core Rulebook

The spell guidelines for wards against magical things are listed with a base range of
Touch, base duration of Ring, and base target of Circle, because a ward with these parameters
wards against creatures with a Might equal to or less than its level. The parameters of the
spell can be changed in the normal way, so that a ward which only protected the magus (Range Personal, Target Individual) for a duration of Moon would have the same final level.

[InfinityzeN (Troy)]

While it is not clearly stated anywhere, General Wards all use the 'Ward Spells Guideline' as pointed out by Raccoon which means their actual perpetrator is effectively (level + 3 Mags). The way described for calculating it however is to modify the level by the change to R/D/T from its default T/R/C

A Personal/Diameter/Individual Ward with a level 10 would affect beings with 20 Might or less and its Formula would be "Base 20, -1 Personal, -1 Diameter".