Ice Age...
Illwinter' age?
Its a javalin/slinger age in my impression ^^
Snow-covered lands should makes for common water magic, and horse-rider not available yet. Only a few mystic telepath with unicorns,employs them as troophorse.
heres 2 spell
Avalanche
Conjuration 8,WWWWFF,Province Disaster (Ritual)
35 Sapphires.
Mountain/Snowcovered land only.
The caster summons the occult power,cause an avalanche strike targeted province,kill down 1/4 population,1/2 patrolling garrison and bestrow a magic site.
Icequake
Evocation 5,WWWEE,Battlefield Enchantment
5 Sapphires,500- Fatigue.
Snowfield only.
Deals 7 cold damage and 3 physical damage to each non-flying unit per turn.
Magic resistance Negates(+3).