While it's an anime-only tale, the life and death of the Iburi Clan is a perfect example of Orochimaru's cruelty. The Iburi Clan were a unique people, as they possessed the amazing power to transform into smoke. However, their ability to shapeshift into smoke was imperfect, as they would often transform unintentionally in dangerous environments. The wind, for example, could cause them to disperse and die in their smoke form. It's why they lived underneath the Land of Fire, where the chance of wind was scarce.
Orochimaru took advantage of the Iburi Clan's dire situation and offered them the chance to better control their powers with his cursed seals. In exchange, Orochimaru used their children as test subjects for his experiments. When that wasn't enough, Orochimaru nearly wiped out the entire Iburi Clan to find a blood source that was capable of giving him their smoke-changing power. Only one member of the Iburi Clan survived, a young girl named Yukimi.
