This is Blythe.
The package said not only were special bonus color tablets included but that bolder colors could be achieved by adding white vinegar. I dyed the mint green dress early on, and then made the mistake of rinsing in cold water, ostensibly to set the color, but in reality washing most of it away instead. I realized this would not be a colorfast method, and the dye on my fingers reinforced that.
But this time I let the dress air-dry on white paper towels and will try pressing with a hot iron to set the colors. Now that I have a candy-colored rainbow of dresses - lavender, pink, light blue, mint, light green and light yellow - I hope to embroider sweet motifs (when my light box arrives) and to add sweet trims.
If the colors do not appear to be safe for Blythe, then the wearing may be limited to a few moments for a photo shoot - enough to capture a living doll pastel rainbow - and then, poof! Gone like unicorns...