Lion and Tiger are top carnivores in the food chain. They have very strong body, sharp nails and teeth and also they run very fast which make them very tough to get hunted by other animals or predators.
Lionsare at the top of the food chain and have no natural predators. There is no animal that hunts them for food, though they may be killed by elephants in defence of their young, or by buffalo whilst trying to hunt them. This, of course, is not predation - these animals are herbivores and do not kill lions to eat them. Lions also sometimes kill each other in fights over territory, but again this is not because they see each other as prey, and if spotted hyenas find a sick or injured lion they will kill it. They will eat it once it's dead, but their main reason for killing it is to reduce competition, not for food - there are far easier meals out there.A dead lion will be fed on by all kinds of scavengers - hyenas, jackals, vultures, marabou storks, etc.