What did the duck say to the drug dealer?
Gimme some of that quack!
Duck's Drug Request: Quack Demand Humorously Revealed!!11!!1!!!1
Explanation
Explain Bear
Listen here, dum-dum. You are so dense that light bends around you. The joke plays on "quack" having two meanings. One is the sound a duck makes and the other is slang for a bad drug.