Mistaken soul involved with denial (10)
I believe the answer is:
delusional
'mistaken' is the definition.
Both the definition and answer are adjectives. Maybe there's a link between them I don't understand?
'soul involved with denial' is the wordplay.
'involved with' indicates anagramming the letters (involved can mean confusing or complex).
'soul' mixed up with 'denial' can make 'DELUSIONAL'.
Can you help me to learn more?
(Other definitions for delusional that I've seen before include "Possibly psychotic" , "Having mistaken opinions" , "Believing unreal things" .)