West was dealer and prempted with a 2♦ call. You are south and you reach 6NT.
Plan the play on ♦J lead.
ADV/+ please hide your answers and please avoid responding too early.
(Beginners, do not attempt. If you do attempt and get it without any help, you show a lot of promise, or you underestimate yourself
If you are stuck: HINT:
Spoiler
:Note: this is meant as a puzzle hand, so please don't argue if it is really intermediate or not. I think as a puzzle, it is best suited here.

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lead ♦J