xyz I keep trying and can't figure it out. This is what i wrote:

enemyDamagedLabel.Modulate = new Color(21, 145, 11, 255);

    TheEpicCookie @xyz is right, it's float (unless you have "raw" enabled on the sprite?)

    so your code SHOULD be:

    enemyDamagedLabel.modulate = Color(0.09,0.56,0.05,1)

    give or take a decimal point.
    (255/max value = 1.0)