TMNT; Monster race question

[Frankywise]

Hi all,

in the TMNT version of the game, some ally refer to the race of Monsters (Seymour Cutz refers to mutant monsters and Man Ray refers to human monsters for example). My question is, how do we know the race of the Monsters? Do we guess or ouse rule it? Some Monsters are obvious but some can be harder to guess. Also there are some Monsters that from the lore are neither human nor mutant (e.g. Krang is an alien from a different dimension and Mousers are robots).

Thanks