^This^.. I'm having trouble understanding why this is so hard for people to get! lol.. The fact that Xur has sold voidfang 4 weeks in a row doesn't necessarily disprove that RNG, but the unlikeliness of it supports the idea that what Xur sells may not be completely random. We're just hypothesizing here using statistic. Is it impossible to get voidfang vesements 4 times in a row? No; but is it unlikely? Yes. Edit: Also, the numbers we're using is the assumption that Voidfangs has a 1/6 chance of coming up when it may not have been programmed that way.