I have a question regarding penetration together with ring spells and aegis of the heart.
Do ring spells need to penetrate?
Lets say I have a ring spell to keep demons below might 10 out, does that spell need to penetrate? My gut feeling is 'yes'.
Do aegis of the hearth need to penetrate?
In some supplements, the penetration for a casted aegis is given, but this isn't always the case. So if I'm inside a hostile aegis, does that spell need to overcome my parma magica? If yes, what then happens when I'm outside casting a spell in to the aegis?
Penetration of Wards has been resolved explicitly only 2007 in
Penetration for the Aegis was not explicitly settled until 2015, and typically campaigns decide for themselves. But the covenants in TtA from 2015 assume that the Aegis needs to penetrate Magic Resistance to affect beings: that is as explicit as it gets now. See for this also https://forum.atlas-games.com/t/the-break-room/102/1.
To be fair it is difficult to come up with a situation where a range personal target individual spell is resisted (I came up with; it could be resisted if it is cast on some other target than the caster and you could do that with Muto Vim).