From D&D Wiki
Prerequisites: Chaotic Alignment
You are the Alpha, the ultimate hunter. Pack animals will follow your lead instinctively, and most other carnivorous beasts will leave you be, as well as those you travel with. Be wary, however, for territorial creatures, and many hyper-territorial beasts will attack you on sight for the threat you possess.
Player may always lead carnivorous pack animals, such as lions or wolves, and may give them basic commands to follow (fight, flee, intimidate, etc.). Non pack beasts, such as certain bears or tigers, will not be so ready to follow and will instead simply leave you alone (unless one can perform a successful intimidation check against them).
Hyper-territorial animals, such as other types of bears or tigers, will attack you on sight in a berserk state, immune to charms and unwilling to converse until the player is out of sight.