A LONG-SHORT, single-instrument mean-reversion on BTCUSDT.BINANCE USD-M that is deliberately COUNTER-CYCLICAL to the factory's momentum book. The latest evidence is decisive: the momentum/trend family — including the proven BTC confluence and the well-built ETH/BTC ratio — has DECAYED in the current recent regime (ratio spread -33% over trailing 11 months, rolling Sharpe +4.9→-7). That decay signature IS a range/anti-trend regime, and the strategy that pays in a range is mean-reversion, not momentum. This is NOT the dead MR template L53 warns about: those died fee_edge because they faded TINY intraday stretches on fast bars whose reversion was smaller than the round-trip cost. Here the fade is on the DAILY bar and triggers only on LARGE deviations (≥2× daily ATR ≈ 4-6% from the 20-day mean), so the expected reversion (≥2-3% toward the mean) is 20-30× the ~0.10% futures round trip — it clears the L53 escape-hatch (reversion >> 3× cost) by a wide margin, stated up front. It is also REGIME-GATED: it fades ONLY when BTC is confirmed non-trending (flat mean, low directional strength), and stands aside in trends — directly avoiding the 'get run over by the trend' failure that kills naive MR, and complementing the momentum book (which owns the trend regime) rather than fighting it. Single-instrument perp with a HARD ATR stop — NO delta-neutral spot-perp spread, so it structurally avoids the cross-account liquidation flaw that just blew up the DOGE cash-and-carry and SOL pair (their nominally-hedged short legs got liquidated because spot gains don't cross-margin the perp short). Long-short (fills the under-weight direction bucket). Three parameters.