Creature in mountain? It may be climbing below you (4)
I believe the answer is:
yeti
'creature' is the definition.
(I've seen this before)
'may be climbing below you' is the wordplay.
'may' becomes 'it' (I can't explain this - if you can you should give a lot more credence to this answer).
'be climbing' is a reversal indicator (in a down clue, letters climb up).
'below' means one lot of letters go next to another.
'you' becomes 'ye'.
'it' backwards is 'ti'.
'ti' put after 'ye' is 'YETI'.
'in mountain? it' is the link.
I am not very happy about this link. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for yeti that I've seen before include "fictional creature" , "It's fantastic being" , "Tibetan wild man" , "Hairy creature of legend" , "creature awaiting discovery?" .)