With the Regio Hook (page 09/10 , Covenants) , i was considering a gateway to Niflheim.
This would be Niflheim as the Primordial Realm of Cold.
Give it a level 09 Aligned aura (page 16 , RoP: Magic) with Ice/Aquam (rather than Ignem/Cold).
Because this is a gateway regio to a primordial realm , i was considering a Realm Interaction effect
that would reduce Casting Score by 27 (Aura x 03) for all Ignem spells that produce heat and warmth and ReAq to create steam.
Gymir Frost-Father (page 78 , RM) being relevant , though his realm is Jotunheim.
Add have some Muspelli to cause trouble.
Would a gateway to Jotunheim be more suitable?
What other creatures or environmental hazards can i include to discourage the magi?
They have various warming spells and can ward against cold.
None are Ignem specialists , being Mentem (changing emotions) & Healing focused.
I would like to have the Covenant aura enhance an emotion (Favourable Aura , page 16).
This will be a +02 Personality Trait Adjustment , (+03 in the regio).
Due to the association of Phlegmatic with Cold , (A&A , page 40):
Loyal would be the most obvious choice in relation to Covenfolk.
Anyone have any other suggestions?