The Wacky Wabbit
The cartoon begins with the fattened version of Elmer Fudd prospecting for gold, singing "Oh! Susanna", except that instead of 1849, the cartoon is set during World War II, with the implication that Elmer hopes to donate the gold to the war effort: "Oh, Susanna, don't you cwy for me, I'm gonna get me wots of gold, "V for Victowy!", not to mention a "Buy US Savings Bonds and Stamps" sign shown early into the short.
Bugs Bunny appears during the second verse and finishes it with Elmer, singing harmony. From that point on, in a role change from the usual, Bugs pesters Elmer without apparent provocation, as he did in Wabbit Twouble, from burying Elmer in the hole he was digging to cutting off Elmer's suspenders and revealing the girdle he's wearing: "Don't waugh. I'll bet pwenty of you men wear one of these."
Instead of fleeing, this time Elmer turns toward revenge, especially when he observes that Bugs has a gold-filled tooth: "I'm came hewe for gold, and I'm gonna get it!" A furious fight ensues, and Elmer comes up the apparent "winner", holding up a gold tooth, saying, "Euweka! Gold at wast! Heh-heh-heh-heh!" Elmer grins and laughs his usual laugh, and at the same time Bugs mocks Elmer with the same words, dropped-"r" and laugh, revealing that his tooth is intact and that Elmer is holding his own knocked-out gold tooth. So now it turns out that Bugs is the actual winner.