Equip elderly fellow to fight the final battle (10)

I believe the answer is:

armageddon

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'the final battle' is the definition.
(I've seen this before)

'equip elderly fellow' is the wordplay.
'equip' becomes 'arm' (arm can mean to equip someone with something).
'elderly' becomes 'aged' (synonyms).
'fellow' becomes 'don' (both can mean an academic).
'arm'+'aged'+'don'='ARMAGEDDON'

'to fight' acts as a link.
This may not be right. Some or all of it may be part of another bit of the clue.

Can you help me to learn more?

(Other definitions for armageddon that I've seen before include "Last war's ending" , "ultimate conflict" , "Ultimate scrap" , "Apocalyptic battle" , "End of the world" .)

I've seen this clue in The Independent.

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