A lot of RNG engines are built that way. It uses your inventory or loadout against you. Diablo III is probaby the best example of it I've ever seen. If you're trying to roll, say, 20% physical damage on a set of bracers, and your skills are all set to do physical damage, you will roll 100 times, and each roll cost you more money and materials and never get physical damage, or if you do it will be only once or twice at something ridiculously low, say 12 or 13%.
Now, bear in mind, there aren't many forms of damage at all: Fire, Cold, Physical, Poison. That's it.
And what makes it so blatant is you'll roll Cold 10 times in a row, then Fire 5 times in a row, then Poison 10 times in a row but you'll never see physical.
But the system is easy to beat. Before you start rolling, just change your skills to fire and BOOM!
20% physical on the 4th roll.