Since I can't find anything in the rules that states you cannot roll a black die out of short range, I'm inclined to think it works at all ranges.
The range ruler disagrees with you. See "Targeting" page 12
But rules/statement on upgrade cards overrule the rules in the books (see golden rule, page 1). This appears to me to be a way to roll black dice at range since it does not specify at what range it works.


