This trick can be used to take down Sifu's toughest enemies in a single hit

sportskeeda.com:

Sloclap's new beat-em-up Sifu gives players a lot of freedom about how to approach the game. The fighting system is not explained directly to the players and is left up to them to figure out.

There is a single attack in the game which can take down even the most intimidating of enemies. The Charged Backfist, when combined with certain weapons, makes mincemeat of enemies, which makes the move an insta-kill option. It does make for a gentler run though as players can breeze their way through the game.

The best unlockable attack in Sifu would certainly have to be the Charged Backfist. The player delivers a solid whack to the opponent's head with or without looking at them. Paired with a bat weapon, it becomes an extremely useful trip attack and makes the player feel more like a badass.

The Charged Backfist becomes an entirely different beast with bladed weapons. Partially charging the attack results in an upward sweep that doesn't do a lot of damage. Fully charging the attack before releasing makes the player dash forward and run the blade through the torso of whoever they're aiming at. This move sacrifices the weapon for an instant-kill.

The player does have to land the strike cleanly to get the kill. The attack can be blocked or avoided and the charge up animation takes some time. This makes it tough to use the attack in regular combat.

It also isn't worth sacrificing a weapon for a regular enemy which makes the move extremely useful in specific situations only.

The trick to executing the attack is to hold on to the sword until you encounter one of Sifu's elite enemies. These enemies talk to the player before the fight, usually if the latter gets too close to the enemy or throws a punch, the cut-scene stops and the fight