Hero sussed most of you out (8)
I believe the answer is:
odysseus
'hero' is the definition.
(I've seen this before)
'sussed most of you out' is the wordplay.
'most of' means to remove the last letter.
'out' is an anagram indicator (out can mean wrong or inaccurate).
'you' with its last letter taken away is 'yo'.
'sussed'+'yo'='sussedyo'
'sussedyo' anagrammed gives 'ODYSSEUS'.
(Other definitions for odysseus that I've seen before include "Homer's wandering hero" , "Greek name for Ulysses" , "Hero of an epic poem attributed to Homer" , "Greek hero of an epic journey home from Troy" , "Homeric wanderer" .)