cases where one is adding a color on top of the same color (E.g. black on black, blue on blue, red on red, etc.);...
understanding the two views with "דרך לכלוך" (coloring destructively). (Wiping one's hands on a towel from grape juice, blood, pomegranate, colored ices, etc.);
Washing Dishes in Situations Related to Pesach;