Tail of the Sun

Tail of the Sun (太陽のしっぽ, Taiyou no Shippo: Wild, Pure, Simple Life) is a 3D action and role-playing video game developed by Artdink and released on the PlayStation.
The player's ultimate objective is to build a tower of mammoth tusks that reaches the sun. To this end, a large map full of various creatures and oddities must be traversed in an effort to locate and gather sufficient food for the tribe to thrive and multiply.
The game was re-released in Japan on PlayStation 3 and PlayStation Portable as a PSone Classic in 2006.