Author: TimFReilly Current version: Milestone 1 Last change: 2020-03-28 05:19:38 Stage: Design

The Curious Reemergence of Castmire

Castmire is a Custom Magic: the Gathering set and setting developed by the Beacon of Creation podcast community. The plane of Castmire is entirely contained in one colossal mansion. This mansion was, until recently, a hub between the planes of the Multiverse. This has filled the mansion with a menagerie of oddities and ecosystems. Its owner, Barstoe, was once a gracious host and trader with the multiverse. At some point, however, he lost control of both the mansion and his faculties. This plane, all but forgotten to the multiverse for decades, is only now being rediscovered by post-Mending Planeswalkers.

The tone of the plane is "spooky noir" meets "Beauty and the Beast animated furniture" meets "Dungeons & Dragons sprawl". As a set designed with the community, its influences will come from many different people. The conceit of the plane embraces this, encouraging a zoo of creatures and a hoard of items from across the many planes of Magic.

Milestone 1

One goal of the relaunch is building to milestones that can be downloaded and playtested. My recommendation is that we design exactly enough cards to build two sealed pools (180 cards) and have multiples of commons to make the packs feel real.

  • 12 Rares (all different)
  • 18 Uncommons (each printed twice)
  • 44 Commons (each printed three times)

I don't feel this card file needs to be exactly color balanced, nor does it have to fully display all potential themes of the set. I think our goal here is not to declare the eventual structure of the set. The goal is to have a playable version of the set with a couple cards with each mechanic.


These mechanics are locked until we hit Milestone 1. After that we can reconsider how they fit in the set.

Visit {cost} (Play this card face down as a land named Unopened Door with "T: Add C." You may turn this card face up by tapping an untapped creature you control and paying this card's visit cost. Visit as a sorcery.)

  • The collapse of the planar portals of Castmire had the side effect of contaminating many of its rooms with the ecosystems of other planes.
  • Explorers of Castmire won't know whether a beautiful Selesyan garden or Atarka's feeding hall will appear behind the next door.
  • All Colors?

Startle (This creature can't attack, block, or activate abilities this turn.)

  • A variety of creatures lurk the halls and rooms of Castmire. Between the castaways from other planes and the overloaded magic seeping into the furniture and furnishings, you never know what you'll encounter next.
  • White/Red/Artifact?


  • Ashiok's arrival has instigated a torrent of spirits and nightmares, causing some creatures to return to extract vengeance on their killers.
  • Our version of Haunting is similar to the Haunt keyword from Guildpact with more variety. In castmire, haunting doesn't only happen when creatures die. Some things can haunt from graveyards, or straight from play!

Investigate (Create a Clue artifact token with "2, Sacrifice this artifact: Draw a card.")

  • Oddities and curiosities abound in Castmire. Can they be touched, broken, and turned into something useful?
  • This mechanic is currently the same as it was in Shadows over Innistrad, with the addition of Eldraine-style Clue cards go to along with the tokens.

Setting and Flavor

Haunted Mansion

Castmire was once a bustling plane, serving as a waypoint and trading post for interplanar travel. With the Great Mending, approximately 60 years ago, the plane's portals were severed and the mansion cut off from the multiverse. Those who thought they would only visit the mansion found themselves cut off from their home plane. The state of the mansion initially degraded into chaos, and many of the visitors died or wandered into the endless hallways. In the decades since, though, a peculiar equilibrium has emerged, with some groups settling in and even raising children. Some refuse to settle and instead search for the fabled Exit that will let them go home.

Animated Furniture and Furnishings

The mansion-plane of Castmire is infused with living magic, allowing it to reconstruct and expand itself. Along with that comes a living crew of chairs, tables, rugs, and more. At one time or another, every fixture and fitting has been known to show signs of life, from sconces to tablecloths to loose floorboards. There's speculation as to what intelligence guides these creatures, as they are often seen working together to help clean and repair the rooms.

A Menagerie of Monsters

Even before Castmire was shut off from the rest of the planes, it was known for its zoos of exotic creatures. With the wardens of these places missing or dead, those creatures have been found roaming the rooms. This ecosystem has been further developed by the trapped travelers on Castmire, who have taken to raising and farming creatures from across these planes. The magic of the mansion seems to abide, and entire wings of the building have been transformed to more closely match the planes from which these fauna and flora originate.

Milestone 1

Date: 2020-03-28 05:19:38

CC 19 20

Date: 2020-03-25 18:01:15

DC 25 26

Date: 2020-03-21 23:51:49

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CC 17 18

Date: 2020-03-17 07:21:15

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DC 23 24 CC 16

Date: 2020-03-14 21:13:44

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CC 14 15

Date: 2020-03-10 05:54:25

DC 21 22

Date: 2020-03-08 06:33:48

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CC 11 12 13

Date: 2020-03-06 04:11:49

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DC 19 20

Date: 2020-03-02 06:22:54

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Date: 2020-02-25 06:58:45

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Date: 2020-02-17 18:39:04

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Date: 2020-02-11 04:26:07


Date: 2020-02-07 03:58:28


Date: 2020-01-27 06:29:48


Date: 2020-01-14 02:27:37

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DC 678

Date: 2020-01-07 07:16:22

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Date: 2019-12-23 06:32:39

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Date: 2019-12-17 03:37:18

This is the first version of Castmire published on