Feat: Craft Magic Castle. Does something similar exist?

[a-d]

I'm interested in the make magic item feats but have been looking in particular for "Craft Magic Castle."
Nothing is coming up.

Should I be looking for Craft Magic Hut or House?

I know, I know, no such thing right? But do you have any suggestions on how such a thing would be done?

Craft Wondrous Item with the formula being:
Huh. I don't know. Figured it to be cost of material component times 100, plus spell level times caster level times 10,000gp with an xp cost of 1/25 of the final price. But now I wonder.

You don't have to forge the sword, shield, or ring to make it into a magic item. So why would you need it for a castle, mansion, house, or mud hut?
Okay, the need for a masterwork weapon might block a mud hut if it isn't somehow a masterwork version of a mud hut. Ceramics maybe?
But then wouldn't Craft Wondrous Item be enough for such a thing?

Is there anything on enchanting houses, castles, towers, etc out there?

 

[Arkhandus]

This stuff is already covered in the Stronghold Builder's Guidebook, a 128-page softcover supplement released by Wizards of the Coast in May of 2002 for 3rd Edition D&D (though equally valid for 3.5 as well, since it has very, very little in it that would be affected by the changes of 3.5).

The Stronghold Builder's Guidebook covers a variety of magical architecture and special features for buildings and other places, as well as stats and details for mundane constructions. It has 2 new spells in it; Augment Object to make objects tougher, and Improved Arcane Lock to let more allies bypass the magical lock it creates. It also includes the Create Portal item creation feat (reprinted from the FRCS) and adds the Landlord feat which grants access to a certain amount of 'free' resources for construction purposes.

It has a bunch of other stuff related to strongholds and such, including mobile strongholds and guards and traps, as well as maps, costs, and descriptions for 5 example strongholds, ranging from the mundane to the extremely magical.

Craft Wondrous Item is the only feat needed to create magical architecture or to enchant existing architecture. Each of the special abilities or properties available for architecture has its own short set of costs and prerequisites, like any other magic item (such as requiring Craft Wondrous Item and Augment Object to create a magically treated wall that's permanently super-durable).