Stuck, irritatingly, in divers places :
13A - Viper's face unsettling thrush (5)
V?E?Y
21A - Sporting blue, if inhaling oxygen, gets energy source (7)
B?O???L
25D - Part of woodland you once ogle (7)
G???E?E
38D - Crossed road outside of Enfield (10)
?V?????S??
&
55A - Divert group playing with dog (9)
S????????
Some of these letters may be erroneous......
Yes, it is pretty pathetic, but I'm pleasantly surprised to have got this far.