A LONG-SHORT, single-instrument, short-horizon microstructure strategy on LINKUSDT.BINANCE (USD-M perp, 15m bars) that trades the intraday convergence of the perpetual toward its own spot INDEX using a genuine NON-PRICE feed: the Binance premium/mark-index basis (mark_price vs index_price, the same quantity the exchange samples to compute funding). Core idea distinct from anything deployed: when leveraged flow pushes the perp to a large PREMIUM or DISCOUNT versus the underlying spot index, that gap is an arbitrage-closable dislocation that reverts on an INTRADAY timescale (minutes-to-hours) as basis arbitrageurs and index-anchored market-makers pull the perp back — a faster, mechanically-different effect than the 8h funding cycle. This is NOT the exhausted funding-EXTREME direction bet on majors (L13): the signal is the instantaneous basis z-score and the exit is convergence to index, not a funding stamp; and it is on a mid-cap major-alt where basis overshoots are large enough to clear fees, not BTC/ETH where they are ~1bp. It is NOT a two-leg cash-and-carry (L28/L1) — it is a SINGLE-LEG directional trade on the perp only, so it pays one ~0.10% round trip, not two. It is NOT pure-OHLCV (L30) — price is only the convergence target; the entry REQUIRES the basis feed. Differentiated from my prior taker-flow reversion (uses basis, not aggressor volume) and from the deployed SOL VWAP reversion (basis-vs-index dislocation, not price-vs-VWAP; different instrument). Deliberately 3-parameter to fight overfit (#1 killer, 229x). Fills three under-represented buckets: long-short direction (14.4%), short horizon (7.9%), and a crypto-native microstructure mechanism the portfolio barely touches.