The Chicken creature spell is a Creature Spell that was cut from the original Dungeon Keeper, likely due to being unbalanced. Not much is known about it, but references are made to it by the Dungeon Keeper Gold manual: From this, we know its effect would have been identical to the Chicken Keeper Spell, but would've been fired as a projectile (possibly using the same sprite and many other projectiles such as Poison Cloud and Freeze, with a possibility to have launched an egg.)