According to the source, Bitcoin (BTC) fell below $85,000 intraday, indicating a test of a major round-number level that traders closely monitor for momentum shifts, source: X post dated December 18, 2025. Round-number thresholds such as $85,000 often act as psychological support/resistance that cluster orders and can heighten short-term volatility around the level, source: Harris (1991) on price clustering; Osler (2003) on order clustering at round numbers. For trade execution, many practitioners seek confirmation via a sustained close back above the breached level to validate a reclaim, or a clear rejection below it to confirm downside continuation, source: Murphy, Technical Analysis of the Financial Markets. The source post did not provide exchange, timestamp of the print, or volume context, so traders should verify the break on their primary spot and futures venues before acting, source: X post dated December 18, 2025.