The baby chicken known as Archie was created when D_2the_avid threw an extra egg he had acquired at a wall, which by chance birthed a chicken. David named the chicken Archie, but when he turned his back for a second, the chicken had disappeared. Archie did nit reappear for another episode when FnD found him standing in the same position he was standing before he disappeared. However, when David turned his back, Archie disappeared again. It was later learned that they chicken could super-stealthily move very long distances in a few seconds, and fit into very small spaces. Thus it is thought that Archie would be an amazing assassin and is employed by FnD, although he has gone on no official missions yet. he currently lives somewhere in Elysium.
Although not directly related to Archie, FMB have a similar full grown chicken living with them. Knighted by FunkMasterBlast personally, Sir Chickenbeak is the chicken esquire of Winterly Rock, only for Rich to murder him a few episodes later.