Storyteller01 said:
Waht happens when critters with natural attacks (such as a minotaur) gain Class levels (say fighter, in the minotaurs case)?
Natural attacks fall into two categories: primary and secondary.
Primary natural attacks are made at full BAB and use the creature's full Strength bonus, while secondary natural attacks are made at full BAB with a -5 penalty and use half the creature's Strength bonus. Neither gets iterative attacks based on high BAB (so a creature with BAB +6 and two claws doesn't get to make attacks at +6 / +6 / +1 / +1, he only gets +6 / +6).
As a normal (standard action) attack, a creature may attack with any weapon it has available - including its natural weapons.
When making a full attack (full-round action) a creature can mix manufactured weapons (which includes unarmed strikes) with natural weapons; when doing so treats his manufactured weapons as primary, and all natural weapons as secondary. He could also just use his manufactured weapons or just use his natural weapons, if he so desired. He can always use all of his natural weapons when he mixes them, unless something he's carrying prevents it (like, for instance, a creature with a claw attack has a shield or sword in that hand).
So, take a minotaur, with BAB +6. He's got a Gore attack as a primary natural weapon, and has a greataxe So, if he makes a standard action single attack, he can gore, or he can strike with his greataxe at his full BAB (+6) and 1.5x his Strength bonus (+6). (Note that the SRD statblock is wrong, here - since the mino only has a single natural attack, it should get 1.5x his Strength bonus on it.)
When he makes a Full Attack, he can elect to just Gore (at BAB+6, Str+6), just use his Greataxe (at BAB+6 / +1, Str+6), or mix them: Greataxe (BAB +6 / +1, Str +6) and Gore (BAB +6-5, Str+2).