Here is a sentence from an endless runner game:
Building hopping chops is a good strategy to avoid unexpected dangers.
The player is advised to leap to the side when she sees any danger or goes near a risky corner.
"Chops" is a term for technical skill. It's usually used when referring to a musician's ability with their instrument, but in this case the game is referring to your skill in hopping as your "hopping chops". It's telling you that a good strategy to avoid unexpected dangers is to get good at quickly hopping to the side.
In the context, building - refers to to increase or strengthen by adding gradually to.
Given your definition of hopping chops (not, to my ear, a phrase outside of the game), I would interpret the phrase to mean that the player should perform hopping chops one after another to increase their strength.
This may consist of holding the key down to build up strength, or to repeatedly press the key (the way you might press space multiple times to jump higher in most games).
It does, however, sound like this is pretty specific to the game. You might consider posting on the gaming stack exchange!
Perhaps it is a combination of these two other answers. Perhaps "chops" refers to a skill. In this case "hopping chops" refers to the player's skill in hopping. "Building" refers to increasing, and so "Building hopping chops" is referring to the process of improving one's skill: learning to hop better. If someone were to ask "What is a good strategy for avoiding danger?" The answer could be that you should improve your hopping skills because hopping is a good way of getting out of danger.
It probably means that you build some "chops" that you can hop on(i.e. stand on).
A chop probably means a piece of wood that is partly buried in the ground, and you can step on the part that reaches into the air. So it's basically a place that you can step on.
And why "hopping"? I'd guess it's because you're going to hop on those chops.