Bats all at once scratching a legendary hero (8)
I believe the answer is:
lancelot
'legendary hero' is the definition.
'lancelot' can be an answer for 'hero' (I've seen this before). I'm not certain of the 'legendary' bit.
'bats all at once scratching a' is the wordplay.
'bats' indicates anagramming the letters (slang for mad).
'scratching' suggests deleting specific letters (some letters are scratched out).
'all'+'at'+'once'='allatonce'
'allatonce' with 'a' removed is 'llatonce'.
'llatonce' anagrammed gives 'LANCELOT'.
Can you help me to learn more?
(Other definitions for lancelot that I've seen before include "K?" , "Arthurian knight, Guinevere's lover" , "A Knight of the Round Table, lover of Guinevere (8)." , "Call tone for knight of Arthurian legend" , "queen's lover" .)