DISCLAIMER
Supernatural and Machida belong to the WB. I got Machida from the BTVS episode "Reptile Boy", though I've made up his powers.
"Sammy!" Dean yelled. His heart raced fearfully. Why didn't Machida just quit while he was ahead? Sam moaned as he forced himself to a sitting position. Machida hissed as he approached. He wrapped a claw around Sam's throat and pulled him to his feet. A group of Sigma Psi Cappas went to surround Dean, but were scared off by his shotgun.
"Some bullets are real, and some are rock salt. No telling which is which," the man warned.
"You have no more cards to play, Winchester," Machida stated. With a hissing snarl, his skin rippled and Sam's eyes widened.
"No! NO!" he shrieked. Dean let out a shot and Machida turned. The Naga's face, which had already been snake-like in appearance, was now introverted into a truly hideous snake visage.
"Aw, man! You're ugly!" Dean exclaimed, before firing again. He went to fire again, only to discover that the shotgun was spent. He then pulled out a pistol and started firing. With a roar, the creature went down. Free, Sam collapsed.
"Sammy!" Dean cried, running back to his brother. "You okay?" he asked.
"Uh, yeah," Sam panted. Machida groaned. Sam quickly reached into his brother's back pocket, forced himself forward and stabbed the snake right in the heart. Then, Dean helped Sam up and they walked out, receiving no trouble from the cult members, who were shocked by the death of their leader.
"Sammy, how'd you know the knife was there?" Dean wondered.
"You always keep your knives in your back pocket," Sam replied. "And it's Sam," he continued.