### Clue: Creature's an example mostly inhabiting beneficial surroundings (8)
### Answer: PLATYPUS 
 ### Explanation: Definition: Creature
 [ A("an" for nouns beginning with a consonant sound) + "type"(an example;something or someone typifying a group of class of things) **minus its last letter**(mostly) **contained in**(inhabiting … surroundings) PLUS(beneficial;having positive advantage or good, as in "a plus factor").