Paleomythic: Stone and Sorcery in the Land of Ancient Mu

From the introduction:

Imagine a world before recorded history, when tribes and kingdoms fought over primordial lands, when warriors struggled against savage and gigantic beasts, and when nefarious priests conceived their evil plans, whilst hidden away in their mysterious stone temples. This is a world where weapons are made of stone, wood and bone, and where armour is a thick hide or fur. It is a world where fabulous gems reward the bold, and where the curious can explore cave cities and discover strange new tribes. This is the era before time, the time that never was, the Paleomythic!