Historical Rules · 23 August 2019
Rule 612.2a
Official source text from the 23 August 2019 Rules release
Most spells and abilities that create creature tokens use creature types to define both the creature types and the names of the tokens. A text-changing effect that affects such a spell or an object with such an ability can change these words because they’re being used as creature types, even though they’re also being used as names.