Historical Rules · 1 October 2009
Rule 309.3
Official source text from the 1 October 2009 Rules release
Plane subtypes are listed after a long dash, and may be multiple words: "Plane -- Serra's Realm." Each word after the dash is, collectively, a single subtype. Planar subtypes are called planar types. A plane can have only one subtype. See rule 204.3m for the complete list of planar types.