All those who love felines, meet the liger, a cross-breed between a male lion and a female tiger. They don't normally show up anywhere in the wild, because lions and tigers generally live in different geographical regions, although there is some evidence that ligers — as well as tigons, the offspring of a male tiger and a female lion — have at some point in the past existed in the wild due to Asian lions sharing overlapping territories with tigers.
Their enormous size — they are much larger than either of their parents, and a male liger can grow up to 3.5 meters in length and about 550 kg in weight, with a shoulder height 45 cm higher than that of a male African lion — is believed to be the result of imprinted genes which normally regulate and arrest the growth in lions and tigers, but which appear to be silenced in ligers, depending on which parent donated which genes.
Contrary to some popular beliefs regarding cross-breeding, neither ligers nor tigons are sterile. They can indeed reproduce, and there have even already been male ligers which have mated with female tigons — unlike a liger, a tigon does not grow to be any larger than a tiger, and tigons are also known to often have neurological defects and quickly develop lots of health problems, commonly including cancer — and have produced further offspring of their own, called litigons.