Move over the U.S. Federal Reserve (Fed), as the Bank of Japan (BOJ) is now likely to cause major shifts in global market flows. That’s the message from Griffin Ardern, volatility trader from crypto asset management firm Blofin.

“I think the BOJ will be the most significant uncertainty factor in the future. Whether it is the Fed or the ECB, their policy paths have been clear, but the BOJ is not, which means that the BOJ is likely to ‘surprise’ us beyond expectations,” Ardnern told CoinDesk.

Since 2016, the BOJ has guided short-term interest rates at minus 0.1% and the 10-year government bond yield at around 0%, known as yield curve control (YCC). It has also set an allowance band of 0.5% above and below the 10-year yield target. In July, the bank said it will allow the yield to move above the cap as long as it stays below 1.0%.

These liquidity-boosting policies have put downward pressure on global bond yields for years, adding trillions of dollars in global liquidity. The persistent easing bias over the years has popularized carry trades, which involve borrowing in yen and investing in high-yielding risk assets.

So, a potential unwinding of the negative interest rate policy and the yield curve control by the BOJ may strengthen the Japanese yen (JPY) and have knock-on effects on risk assets, including cryptocurrencies. The tightening cycles of the Fed, ECB and others are widely believed to have peaked. Meanwhile, the BOJ is yet to move the needle on rates.

“Once the BOJ begins unwinding the ultra-easy policy, many assets previously obtained through the JPY-USD arbitrage channel [carry trade] may be sold off to repay debt denominated in JPY. That, in turn, may have an unexpected impact on the crypto market,” Ardern said.

Charles Schwab voiced a similar opinion early this year, saying the carry trade can unwind quickly, leading to “outsized cross-market volatility.”

Most economists polled by Reuters between Sept 8-19 poll expect the BOJ to end the negative interest rate policy and abolish the curve control program next year.

According to ING, the central bank may drop hints of the eventual hawkish move on Friday.

“The BoJ is likely to stay pat [on Friday]. It could, however, send a subtle hawkish message to the market after higher-than-expected inflation and a weak JPY, combined with rising global oil prices, pushed inflation up further,” ING said, per ForexLive.