Only the large mammals becomes the prey of king of jungle, include buffaloes, wildebeests and even elephants.
They usually group together for hunting, lioness mainly lead the hunting, male lion take care of younger ones at that time. Once they found herd of its prey focused for the closest prey and make sudden attack.
The sudden and powerful bite at neck cause death to pry in no time, no chances for escaping. For larger more larger preys like giraffes or elephants they attack from behind. Lion usually make hunting at night to get advantages of reduce visibility at that time.