Historical Rules · 22 April 2021
Rule 612.2a
Official source text from the 22 April 2021 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.