is there a reason for changeing colors of some pokemon sprites
like Tentacruel tentacles what is the color now brown or gray
or they like change it somthime or is it like the collor of koffing in HeartGold, SoulSilver
There's no real reason really, it's more that Game Freak just changes as their technology improves, which means why some of the sprites were terrible years ago, but have improved greatly. The same goes with colours. Certain redesigns of sprites also don't fit with colours so they change it slightly. Plus there's also shiny Pokemon, too! Those go through the same process too. But ya, there's no special reason, it just changes as technology improves. Nevertheless, questions like this could fit in the Quick Questions sticky next time, although it should mainly be about in-game things.