Sure, here's how it works:

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You have 1 BTC priced at $10,000.

You're worried that BTC price will decline in the future.

You securitize 1 BTC on https://as.exchange/ and issue 2 Tranched Value Securities (TVS).

Each TVS can claim 50% of BTC market price, or a fixed value of $5,000, whichever is greater; one TVS is Senior and the other is Junior, where Junior TVS can claim anything, only if Senior TVS's claim was satisfied in full.

You sold Junior TVS because you expected BTC price to decline.
Another person bought Junior TVS from you because s/he expects BTC price to increase.

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Next week BTC price falls to $8,000 (-20.0% return).

Senior TVS price becomes: max($8,000 x 50%, $5,000) = $5,000 (0.0% return).
The Junior TVS price becomes: max($8,000 x 50%, $5,000) = $5,000, but then the total value of TVS would be $10,000, leading to arbitrage opportunities, hence ...
Junior TVS price becomes: $8,000 - $5,000 = $3,000 (-40.0% return)

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Next week BTC price rises to $11,000 (+37.5% return).

Senior TVS price becomes: max($11,000 x 50%, $5,000) = $5,500 (+10.0% return).
Junior TVS price becomes: max($11,000 x 50%, $5,000) = $5,500 (+83.3% return).