On the border a month of malicious damage (6)
I believe the answer is:
mayhem
'malicious damage' is the definition.
'mayhem' can be an answer for 'damage' (thesaurus). I'm not sure about the 'malicious' bit.
'on the border a month' is the wordplay.
'on' says to put letters next to each other.
'the border' becomes 'hem' (I've seen this before).
'a month' becomes 'may' (May is an example).
'hem' after 'may' is 'MAYHEM'.
'of' acts as a link.
Can you help me to learn more?
(Other definitions for mayhem that I've seen before include "Violent damage, chaos" , "Chaos, violent disorder" , "State of great confusion and disorder" , "Havoc - chaos" , "Chaos, confusion, destruction" .)