What tactic involving a pretended retreat did the Normans use at Hastings?

The Norman tactic was called a feigned flight.

A feigned flight is a deliberate, false retreat designed to lure an enemy out of a strong defensive position. At Hastings, Norman troops appeared to flee in panic, encouraging some English fighters to pursue them down the slope. The Normans then turned back and attacked the pursuers, who had become separated from the shield wall.

The English defensive formation was extremely difficult to break by direct assault. Harold’s infantry held high ground behind overlapping shields, while the Norman army combined infantry, archers, and cavalry. By drawing parts of the English force away, the feigned flight could thin the shield wall and create openings for renewed attacks.

Medieval sources attribute the tactic to the Normans, and many historians accept that it was used during the battle, possibly more than once. However, the details are not perfectly certain: some scholars have argued that later writers exaggerated or developed the story to explain Norman movements. The tactic did not single-handedly decide Hastings, but it helped exploit weaknesses in the English position.