Deep inside the bowels of a dark cave in central Europe, a noise rouses a fierce creature.
Sleeping on its bed, a giant cave bear opens one eye, alert to any intruder.
It stands, lifting its massive 400kg frame and bares its teeth.
In front of it is an equally sized cave lion; a giant predatory cat, and the cave bear's mortal enemy.
Only one will survive, while the bones of the fallen will litter the cave floor for millennia.
New evidence reveals how such titanic struggles likely took place in caves across central Europe in the Upper Pleistocene epoch, which ended around 11,500 years ago.
While excavating caves in Germany and Romania, scientists have unearthed the bones of large numbers of cave bears, a now extinct species that stood bigger than today's grizzly bears.
The bears' bones, claw marks they left in the caves in which they lived, and even the beds they slept on, paint the best picture yet of how these magnificent creatures once lived.
But more than that, researchers have also uncovered the petrified bones of the cave bear's foe, the Pleistocene cave lion.
More than 25% bigger than today's African lions, the cave lion was itself an impressive predator, one that may have specialised in hunting cave bears for food.
Details of the two massive animals' remarkable battles have been released by palaeontologist Dr Cajus Diedrich of PaleoLogic, based in Halle, Germany.
