Extremely Difficult or Challenging; Devious
This page is the CodyCross answer for the clue below from Chile, Group 2295, Puzzle 1 (Valdivian Rainforest).
Question
Extremely Difficult or Challenging; Devious
Answer
FIENDISH
Word Meaning:
FIENDISH — Sinister; evil; like a fiend.
Definitions from Wiktionary.