I haven't been playing long, but I'm still finding new sites I have never seen and that is great. I even appreciate the time I "discovered" one of those eeevil sites when it horror marked my prophet and pretender the same turn...
Here are a couple of ideas which might be fun for new magic sites that I haven't seen suggested anywhere:
+ Halls of Elevation: provides X% bonus for Empowerment
+ Empty Altar: provides a +X Call God bonus (I need this way way too often)
+ Mystic Archive: provides a +X Research bonus
+ Wormhole: a 1-way #neighbor to a random map province
+ Storm Home: permanent Storm effect for any combat (other Versions for Haunted Forest, Fog Bank for Mist, Energy Vortex for Antimagic, Holy Ground for Bless, etc)
+ Angered Earth: chance of an Earth Attack at any time (other Versions for Flames from the Sky, disease, Call of W/W, etc?)
+ Black Market: reduced (tax) income, chance an item will be "pickpocketed" from a commander, can recruit Villain/Assassin?
+ Echo Canyon / Resonant Woods reduces/increases the effect of all song/tunes (Soothing, Healing, etc)
+ Pirate's Lair: Can recruit Pirates and Captain (seacoast)
and how about a way to create new sites in a mod
Silhouette
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