I’ve been adding some colors to my walleye plastic collection and one is a “changeable” color, blue crawdad. In the hand this color is a thin smoky blue. Drop it in the river and it turns a pale transparent brown. Here in the picture you can see it done as a stand alone color and there is another version done as a belly/tail color under motor oil.
I’ve had some success using this color, hence the need to put more in the box. Its a good cloudy day color for me.