Whenever a Robert E. Howard character was setting out into the unknown, you never knew when he would run into some creature of the past.

Mammoth: Those magnificent great cold weather elephants of the Pleistocene. James Allison mentions them as Hunwulf encountered them in “The Garden of Fear.”

“I gave them a wide berth, giants too mighty for me to cope with, confident in their power, and afraid of only one thing on earth. They bent forward their great ears and lifted their trunks menacingly when I approached too near, but they did not attack me.”

Hunwulf spooks the mammoths with fire so they trample the field of blood-sucking flowers.

Mammoth might have lived in the steppes to the east of Hyperborea in the Hyborian Age. Their range obviously spread after the Hyborian Age.

Pterosaur: Brule mentions to Kull in “The Shadow Kingdom”:

“Men took for a sign and a standard the figure of the flying dragon, the winged dinosaur, a monster of past ages, which was the greatest foe of the serpent.”

Cave Lion (Panthera spelaea): Once thought to be a sub-species of the modern lion, genetic analysis has shown it to be a separate species. It ranged from Spain to Alaska 470,000 to 14,000 years ago.  It could reach a length of 8 ft, 2 inch, height of 3 ft, 11 inches, and weigh up to 747 lbs.

This would have been the lion that Conan faced in “Tower of the Elephant.” The modern lion colonized the Balkans around 6,000 years ago and extinct by the 4^th Century A.D.

Cave Leopard (Panthera pardus spelaea):

“Among the furs on the dais was a gorgeous spotted skin, whose predominant hue was golden. It was not a clever copy, but the skin of an actual beast. And that beast, Conan knew, had been extinct for at least a thousand years; it was the great golden leopard which figures so prominently in Hyborian legendry, and which the ancient artists delighted to portray in pigments and marble.”- “The Devil in Iron”

These Ice Age leopards were bigger than the ones today. Their prey might have included the Cave Bear.

Auroch (Bos primigenius): The Cimmerian bull. The wild progenitor of modern day domesticated cattle. It only became extinct in 1627. The auroch was domesticated during the Neolithic. It was found from Britain to Korea. North Africa to India. The bulls could reach 61-71 inches at the shoulders, and weigh up to 3,3100 lbs.

Robert E. Howard told P. Schuyler Miller and John D. Clark that Conan traveled to the unknown western continent. North and South America would have been full of Pleistocene mega-fauna. Conan might have explored sparsely inhabited areas hunting the way Esau Cairn did in Almuric. There would have been Dire Wolves, massive ground sloths, giant moose, mastodons, Columbian mammoths, the saber-tooth tiger Smilodon. Conan liked enjoying civilization but he had no problem hunting in the wilds.