One pulls up to mythical realm (6)
I believe the answer is:
asgard
'mythical realm' is the definition.
(home of the Norse gods)
'one pulls up' is the wordplay.
'one' becomes 'a'.
'pulls' becomes 'drags' (drag is a kind of pull).
'up' shows that the letters should be reversed in order (in down clue: letters go upwards).
'drags' written backwards gives 'sgard'.
'a'+'sgard'='ASGARD'
'to' acts as a link.
(Other definitions for asgard that I've seen before include "land fit for heroes" , "Heavenly place" , "mythological region" , "Heavenly dwelling of the Norse gods" , "Famous Irish yacht from the old Norse heaven" .)