Wanna buy a duck?

[midnightcoder]

The game starts with a bunch of people, the first four of whom are named A, B, C, and D.

A to B: Wanna buy a duck?
B to A: A what?
A to B: A duck.
B to A: Does it quack?
A to B: Of course it quacks, it's a duck.
B to C: Wanna buy a dog?
C to B: A what?
B to A: A what?
A to B: A duck.
B to C: A dog.
C to B: Does it bark?
B to A: Does it quack?
A to B: Of course it quacks, it's a duck.
B to C: Of course it barks, it's a dog.
C to D: Wanna buy a toad?
D to C: A what?
C to B: A what?
B to A: A what?
A to B: A duck.
B to C: A dog.
C to D: A toad.
D to C: Does it hop?
C to B: Does it bark?
B to A: Does it quack?
A to B: Of course it quacks, it's a duck!
B to C: Of course it barks, it's a dog!
C to D: Of course it hops, it's a toad!

Continue until the entire system collapses. Get creative with the objects. A mother. A car. A third world country. Enjoy!