Added to the silly scare that in the end I quashed (9)
I believe the answer is:
increased
'added to' is the definition.
The definition and answer can be both related to change as well as being past participle verbs.
Perhaps you can see an association between them that I don't see?
'the silly scare that in the end i quashed' is the wordplay.
'the silly' indicates anagramming the letters.
'that in' means one lot of letters goes inside another.
'quashed' indicates an anagram (quash can mean to smash up).
'scare' is an anagram of 'creas'.
'end'+'i'='endi'
'endi' with letters rearranged gives 'ined'.
'creas' going inside 'ined' is 'INCREASED'.
Can you help me to learn more?
(Other definitions for increased that I've seen before include "R [ROSE]" , "Made greater" , "Went up" , "Made bigger or more" , "Grew greater" .)