Rage powers (if barbarian) or bloodine powers (if bloodrager).
Q370: Is there a way to make a familiar carried by me threaten adjacent squares? As far as I can tell, familiars are either tiny/diminutive (meaning they don't threaten) or small (meaning they can't be carried). Perhaps an item or feat or archetype gives a workaround?
Q371: Can you Bull Rush a creature off a cliff? If so, does it get to make an additional check to counter this or something?