Ryu's nj. HK (Street Fighter II: Hyper Fighting)
This might be in contention for the highest priority normal in Street Fighter history. This will stuff ANYTHING that isn't invulnerable all the way up.
Million Arthur got Iori as a guest character. Here's how they made his j.4b work as an anime crossup. Look a few inches under his knee for a surprise
Karnov's Revenge has a tendency to adjust priority for many of characters' grounded heavy normals only after active part ends. The game has many scary attacks because of that but imo the most bonkers one is this:
Marstorius' cr.HK is pretty much the only sweep in the game that follows the rule explained above. It has the 2nd longest range, comes out twice as fast as other sweeps, stays active for 8 frames and can be cancelled on both hit and block. If he manages to score a knockdown with it, he can close the gap right away with his dash lariat or run grab and start his mixup game for scoring command grabs(!) and probably winning the match. Truly scary... and truly awesome! Just keep him away with fireballs.
Hits low, impossible to punish on reaction, and also cancellable. A normal should be fast, long range, or high priority, but never all three. This one's all three and more.