Cruelly taunt men, throwing ball in volcano (5,4)

I believe the answer is:

mount etna

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'cruelly taunt men throwing' is the definition.
I know nothing about this answer so I can't tell whether this works.

'ball in volcano' is the wordplay.
'ball in' becomes 'mount' (I can't explain this - if you can you should give a lot more credence to this answer).
'volcano' becomes 'etna' (Mount Etna).
'mount'+'etna'='MOUNT ETNA'

Can you help me to learn more?

I've seen this clue in the Sydney Morning Herald.

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