Season of goodwill yet I duel anyway (8)
I believe the answer is:
yuletide
'season of goodwill' is the definition.
'Yuletide' can be an answer for 'season' (Yuletide is an example). I'm not sure about the 'of goodwill' bit.
'yet i duel anyway' is the wordplay.
'anyway' indicates an anagram.
'yet'+'i'+'duel'='yetiduel'
'yetiduel' is an anagram of 'YULETIDE'.
Can you help me to learn more?
(Other definitions for yuletide that I've seen before include "Old word for Christmas season" , "Present time" , "Christmas time" , "Old word for the Christmas festival - a log is named after it" , "time for feast" .)