For 10 points, name this poison that meth kingpin Walter White packages in a cigarette on Breaking Bad.
An old man knocks a burrito containing this substance to the ground after it is given to him by his nephew. A character played by Lavell Crawford steals a sample of this substance during a patdown; after it is returned, it's hidden behind an electrical outlet, while a decoy for it is planted in a Roomba. A character claims that this substance is actually chili powder in an appearance in which it creates a smell like head cheese. A woman dismissively comments "of course we're not doing business with him" before a closeup shot of what is eventually revealed to be this substance. An (*) illness believed to be caused by this substance is actually caused by Lily of the Valley berries, which are shown in the closing shot of the season-finale episode "Face Off." In "Felina," this substance is added to "that Stevia crap" that Lydia Rodarte-Quayle uses to sweeten her tea, resulting in her death. For 10 points, name this poison that meth kingpin Walter White packages in a cigarette on Breaking Bad.
An old man knocks a burrito containing this substance to the ground after it is given to him by his nephew.
ricin [or the ricin cigarette; accept methamphetamine before "sample" but not afterwards]