Historical Rules · 22 July 2016
Rule 306.3
Official source text from the 22 July 2016 Rules release
Planeswalker subtypes are always a single word and are listed after a long dash: “Planeswalker — Jace.” Each word after the dash is a separate subtype. Planeswalker subtypes are also called planeswalker types. Planeswalkers may have multiple subtypes. See rule 205.3j for the complete list of planeswalker types.