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Ironically I sound of armour shining,

You've me on, the town is dining,

Dancing shepherds will rejoice

If I'm in colour you've no choice

For it is time my dear friends all

To it me call.

'If you're in colour? You're always in colour!'
'Not when the lights are off - then everything is black.'
'Isn't black a colour?

Riddle Answer A Night

Riddle Explanation

ironically I sound of armour shining - night and knight, as in a knight in shining armour, are homophones.

you've me on, the town is dining, dancing - to have a night on the town.

dancing shepherds will rejoice if I'm in colour - red sky at night, shepherd's delight, red sky in the morning, shepherd's warning, is an old expression implying the sunset sky colouring indicates the next days weather.

sing before breakfast, you'll cry before night, a proverb speaking of the changeability of moods.

you've no choice for it is time my dear friends all to it me call - to be time to call it a night.