Fighting together and all about to die (6)
I believe the answer is:
allied
'fighting together' is the definition.
(I've seen this in another clue)
'all about to die' is the wordplay.
'about' indicates anagramming the letters.
'die' with letters rearranged gives 'ied'.
'all'+'ied'='ALLIED'
'and' is the link.
(Other definitions for allied that I've seen before include "Joined together for a purpose" , "Joined together for mutual support" , "Affiliated" , "(Of nations) working together" , "Joined to, combined with" .)