A hypo snow is a combination of a line bred morph such as hypo and a co-dom gene such a snow. To produce you need to breed a hypo to a snow. 50% of the offspring will be snow hypos. Also since line bred traits result from breeding two leopard geckos that have the colors one wants the offspring to exhibit. There is a good chance that a snow X hypo offspring will look a mix of high yellow, normal and hypo. Since only on parent is hypo and the other ones phenotype is technically normal although it looks different since its a snow.