Complex sentence: About 250 locals from in & around the Anaconda & Butte areas were used as zombie extras, although 500 Montanans showed up for audition, including about half from Bozeman, Missoula & Helena.
Split into simpler sentences: About 250 locals from in & around the Anaconda & Butte areas were used as zombie extras. Although 500 Montanans showed up for audition, including about half from Bozeman, Missoula & Helena.