Adventure tours always most odd (8)
I believe the answer is:
queerest
'most odd' is the definition.
(I've seen this in another clue)
'adventure tours always' is the wordplay.
'adventure' becomes 'quest' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'tours' indicates putting letters inside (to tour can mean to go around).
'always' becomes 'eer' (poetic way of saying ever).
'quest' going around 'eer' is 'QUEEREST'.
Can you help me to learn more?
(Other definitions for queerest that I've seen before include "superlative form of rum" , "Most unusual" .)