Frostgrave RPG

[Timeshadow]

I'm thinking of running a pathfinder rpg using Frostgrave as the main local.

I have a few ideas about why spell-casters will be central other than the obvious that there is a lot of magic stuff here. To enter and leave most "districts" of the huge ruined city players will need to pass wards. This will involve a minimum rank in knowledge arcana and a minimum caster lvl so if the wizard/caster is ko'd you will not be able to leave. This will encourage players to have multiple casters. These wards only work on sentient creatures so many animals and monsters can move freely between areas. The wards also dispel any active non permanent spells on anyone/thing who pass through them.

This leads to communities eventually forming just inside the edges of Frostgrave, and to "bases inside the "city" proper.

Anyone have some good ideas/effects that I could use for the campaign?

I'm thinking the ancient city was huge and covered most of the northern half of the continent (which of course is covered in a magical glacier of nearly never-melting ice). Noone knows why the glacier is retreating or can decern any pattern in what districts will be uncovered.