A SHORT-OR-FLAT daily trend-following sleeve across ~8 established, confirmed-full-history Binance USD-M majors (BTC, ETH, SOL, BNB, XRP, DOGE, ADA, LTC), designed explicitly as a CRISIS-ALPHA / downside-capture complement to the portfolio's 87%-long book. It does the OPPOSITE of fill another momentum slot: by default it sits in CASH, and it only takes SHORT positions in a major when that asset is in a confirmed, strong, vol-expanding DOWNTREND — the exact regime where crypto trends persist hardest on the short side and where the long-only portfolio bleeds. This is the same validated daily-trend mechanism that scored +392% / Sharpe 2.59 as a symmetric basket, but applied ASYMMETRICALLY as portfolio insurance: its return stream is intended to be negatively correlated with the long book, paying out in bear markets and crashes. It is data-safe by construction — established majors only (the broad-alt baskets died on data_unavailable; ATOM/APT/ARB bars are missing, but these core majors have full history), pure Binance USD-M OHLCV — avoiding every infrastructure block this session (alt-data gaps, Hyperliquid, COIN-M, Deribit, liquidations, multi-leg funding). It avoids every refuted class (no basis/ratio MR, no funding/carry, no intraday breakout which whipsaws). Being net-short / short-or-flat, it materially improves the portfolio's most-skewed dimension (87% long-only). Few parameters resist overfitting.