Feud may bring ruin for all in Malta's capital (8)
I believe the answer is:
vendetta
'feud' is the definition.
(I know that vendetta is a type of feud)
'ruin for all in malta's capital' is the wordplay.
I cannot quite see how this works, but
'ruin' could be 'end' (ruin something means to end it) and 'end' is present in the answer.
This may be the basis of the clue (or it may be nonsense).
'may bring' is the link.
Can you help me to learn more?
(Other definitions for vendetta that I've seen before include "A prolonged feud, associated with Sicily" , "Private feud" , "Prolonged bitter quarrel" , "Long bitter row" , "Lasting feud associated with Sicily and mafia" .)