Invasion of the Idiot Dog Brain / Bad, Bad Rubber Piggy

S1, E8: In a mechanical mishap, Gir becomes part of the security core of the house. The house takes off and runs through the city leaving a trail of destruction in its path. It seems that Gir's sole interest is in obtaining tacos. / Zim realizes that the only way to get rid of Dib is to send a hunter destroyer machine back in time to alter his past. But the destroyer is incompatible with his time machine and the only object that can make the ultimate trip is Gir's rubber piggy.