Some Pathfinder love...

 My favorite region in Pathfinder's Golarion setting is the Realm of the Mammoth Lords (big surprise to anyone who knows me).  The whole region is a giant Siberia like tundra that's split by deep, steamy valleys that contain mega fauna.  It's also where the Kellid barbarians are from.  They have a history of raiding any local giant tribes that they can and capturing young giants to raise as their own, thus strengthening their tribe and increasing their prestige.  With such a practice taking place I can only assume this sort of thing would happen every great once in a while...

Giant’s Blood (Human)

In your veins thunders the blood of giants. Somewhere tangled in the roots of your ancestral tree is a giant, most likely a guff. Once per day you can call upon the power of your birthright and re-affirm an ancient connection between your tribe and the giantfolk.

Prerequisites: Kellid (Human), Realm of the Mammoth Lords affinity.

Benefit: You can use enlarge person once per day, using your character level as your caster level and affecting yourself only.

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