The morning after a rousing game of Mafia the Drinking Game at Y-san's pad (aka the Game Pad ;P), the neighbors reported a fire in the storage shed. The police investigation squad found Sinistral's burnt body in the storage shed. The shed had one door and a window that was an open rectangle lined with bars 3 inches apart. The door of the shed (which opened inwards) was blocked by a solid cement block that was 1m by 1m by 1m. The police determined that the block was so heavy that no one person could lift or move the block by themselves. The autopsy revealed that Phaze had died from asphyxiation by smoke inhalation (the usual cause of death in fire incidents). But they couldn't figure out how in the world he could have gotten himself trapped in the shed with the block blocking the door...
Sinistral had left the party at one point to go look for some duct-tape to tape Phaze's mouth shut with...he had gone out to the storage shed and hadn't come back. Everyone had been so out of it at that point that no one really noticed until morning...
Y-san, who had an outstandingly high alcohol tolerance for an Asian girl, went out to the scene of the crime. She looked at it for a few minutes and then asked several of the bulky police officers to lift up the block a little so she could look at the bottom. Sure enough, as she had thought, there was a piece of plastic stuck to the bottom of the block.
She knew that TC, who had been issuing death threats to Sinistral was the murderer, and being underage, he hadn't been invited to the party at her pad. And now she new how he did it.
How did TC kill Sinistral?