I'm trying to understand how the Vigilante class works. If a Vigilante chooses an archetype, can it still be an Avenger and get full BAB? For example, a Warlock Avenger?
So what your looking for in the archetype is if it replaces vigilante specialization the two basic one being avenger and stalker you'll notice in warlock mystic bolts replaces vigilante specialization. So no you could not be a warlock avenger.