I am now of the opinion that an animatronic would be a massive waste of money, tons of smoke, noise and lighting effects will be enough. Hopefully it's hard to spot, or at least you're not guaranteed to see it. Almost like it could be a myth.
Would also make sense if there was something else in the barn on the other side for guests to look at when facing that way. Obviously there will be theming but something else of substance would be cool.