Blood Feud is the twenty-second episode of Season 2. It was originally broadcast on July 11, 1991. The episode was written by George Meyer and directed David Silverman. The episode includes the debut of the Olmec head Xtapolapocetl, which would become a common background prop in the Simpson home. It features several reference to the movie, Citizen Kane and songs such as, “Iron Man” by Black Sabbath.
Homer discovers that Bart has a rare blood type that can save Mr. Burns’s life, Homer convinces Bart to give blood (in the hopes that Burns will give The Simpsons a cash reward), but when all Mr. Burns gives Bart is a “Thank You” card, Homer writes a nasty letter to his boss…which ends up getting sent to Burns by Bart.