Technically
Heterozygous describes the pairing at one locus (for one simple trait) so technically a snake can not be het for a combination. However, that is commonly used, and accepted to mean that the snake is het for any traits that are required to make that combo.
For example, a "normal het snow" is het for anery and amel, and an "amel het snow" is expressing amelanism (of course) and it is also het for anery.
So, a "snow het for blizzard and bloodred" is expressing anery and amel, and is also het for charcoal and bloodred. By the above usage of the term, the snake is also het for pewter, among other things...
how do you get a snow het for blizzard and bloodred???
I have a bloodred het for anery, amel and charcoal (her father was a pewter, her mother was anery het bloodred, and one of these two was also het amel) There are several ways you could get a snow het for blizzard and bloodred, if I were to breed my female to a charcoal het for amel and anery, any snows to come out of the mix would be at least het for blizzard and bloodred.
and can you get a charcoal het for pewter? and what would you have to breed with the charcoal het for pewter to get pewters???
Pewter is the combination of bloodred and charcoal. A "charcoal het pewter" could be bred to anything that is carrying and/or expressing both charcoal and bloodred: normal het pewter, charcoal het blood, blood het charcoal, and pewter.