Fliff has released a Week 1 NFL betting guide featuring expert picks and odds for the top three matchups. The guide is available using the promo code DEADSPIN, which offers users exclusive access to the betting lines. The guide highlights key games expected to draw significant attention from fans and bettors. It includes detailed analysis and predictions for the most anticipated matchups of the week. The promo code is valid for a limited time, encouraging users to take advantage of the offer before it expires.