"Blitz/Guardian" chao are actually two-tone white chao, which can be gotten by breeding a normal colored chao with a white colored chao(two-tones can be made with all colors, along with shiny versions of them).
You might also end up with a Shiny Normal colored chao, which is the same thing as your normal chao color, but shiny, or the Monotone Color-changing chao, which is born all white, but will change color depending on what kind of chao you'll make: Neutral Run, Fly, and Normal will be based on what their main body color is, Neutral Swim and Power will be based on the highlights/markings(not their main body color), all Dark Chao will be the color that their highlights(Ex: Dark/Run/Run will be red) are. All Hero Chao are white though. -_- The 3 Chaos Chao are also white, but I heard the Dark Chaos Chao has purple eyelids or something.