The critical level for the Nasdaq 100 appears to be around the 200-day moving average, which currently aligns near 20,385. If the index breaks below this level, it could signal further downside risk, while staying above it might encourage bullish momentum. 

Additionally, historical data shows that when the Nasdaq 100 closes below its 200-day average after an extended run, it often leads to significant drawdowns, making this level crucial for monitoring potential market shifts.