What's it like when a .177 Pellet hits? Mike Tyson Baby!

The exact amount of energy produced by a .177 pellet fired from an RWS Air King air rifle will depend on a number of factors, including the weight of the pellet, the velocity at which it is fired, and the specific characteristics of the rifle. However, as a general rule, a typical .177 pellet fired from an air rifle will produce muzzle energy in the range of 8 to 20 foot-pounds.

To give you a more specific answer, the RWS Air King air rifle is available in a few different models with varying muzzle velocities and energy outputs. For example, the RWS Air King Model 54 fires .177 caliber pellets at a muzzle velocity of up to 1,100 feet per second, producing around 17 foot-pounds of muzzle energy. The RWS Air King Model 350 Magnum fires .177 caliber pellets at a higher muzzle velocity of up to 1,250 feet per second, producing around 23 foot-pounds of muzzle energy.

Again, the exact energy produced by a specific pellet fired from an RWS Air King air rifle will depend on a number of factors, and it's important to always follow proper safety precautions and use appropriate targets when shooting any type of firearm or airgun.
17 foot pounds compared to things for reference something interesting also
Sure! Here are a few comparisons to give you an idea of the amount of energy produced by a typical .177 pellet fired from an RWS Air King air rifle with a muzzle energy of around 17 foot-pounds:

This is roughly equivalent to the energy produced by a heavyweight boxer's punch.
It is also about the same as the force required to bend a standard 1/2-inch steel rod with a pair of pliers.
Another way to think about it is that it would take a force of about 17 pounds applied over a distance of one foot to produce the same amount of energy.
For a more practical comparison, a 17 foot-pound air rifle should be suitable for small game hunting and pest control at relatively short ranges, but may not be powerful enough for larger game or long-range shooting.
Again, it's important to always follow proper safety precautions and use appropriate targets when shooting any type of firearm or airgun.