The character wins the loyalty of an animal, provided that the character's heart is true. The spell functions only if the character actually wishes to be the animal's friend. If the character is not willing to treat the animal as a friend (for example, the character intends to eat it, or to use it to set off traps), the spell fails. An animal's loyalty, once gained, is natural (not magical) and lasting.

The character can teach the befriended animal three specific tricks or tasks for each point of Intelligence it possesses. Typical tasks are coming when called, rolling over on command, fetching, or shaking hands. They cannot be complex (complex tricks, such as accepting a rider, require the Handle Animal skill).

At any one time, the character can have only a certain number of animals befriended to the character. The character can have animal friends whose Hit Dice total no more than twice the character's caster level. The character may dismiss animal friends to enable the character to befriend new ones.