Historical Rules · 27 September 2013
Rule 308.2
Official source text from the 27 September 2013 Rules release
Tribal subtypes are always a single word and are listed after a long dash: "Tribal Enchantment -- Merfolk." The set of tribal subtypes is the same as the set of creature subtypes; these subtypes are called creature types. Tribals may have multiple subtypes. See rule 205.3m for the complete list of creature types.