The most common and most likely answer to this crossword clue is the 8 letter word RAVAGING
I've seen this crossword clue in The Guardian
R
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V
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Buddy explains!
The straight part
We know that "It’s destructive" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case it’s destructive = ravaging.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does RAVAGING mean?
RAVAGING verb- To devastate or destroy something.
- To pillage or sack something, to lay waste to something.
- To wreak destruction.
- The act by which something is ravaged.