They're probably just really efficient, if you join the jp ship, you'll see a lot of 1/1 rooms because they are solo grinders. So you can imagine that a lot of players over there just know what they want to do, they don't stop until they get the results they want, and they do it as efficently as...
The amount of rainbow skins and modifications is impressive, but I've yet to find anything related to rainbow LED on weapons such as Mechgun, Sniper, Shot, or anything of the sort being modified.
For an example, the color adaption (for Mechguns) would go around the LED and would look...