The most common and most likely answer to this crossword clue is the 5 letter word YETIS
I've seen this crossword clue in The Daily Telegraph
Y
E
T
I
S
More clues leading to the result YETIS
- Mysterious figures still on island
- … even though island has these legendary creatures
- More than one mythic creature still lives
- Mythical creatures still found on island
- Creatures you expect to interest scientists first of all
- In spite of everything, I start to search for legendary creatures
- Fantastic creatures one’s cowed by nonetheless
Buddy explains!

The straight part
We know that "More than one mythic creature" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case more than one mythic creature = yetis.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does YETIS mean?
YETIS noun- An unidentified humanoid animal said to live in the Himalayas