
When filming the battle of Helm's Deep, the filmmakers used a computer program called "Massive," created by Steven Regelous. It uses Artificial Inteligence, AI, where each CG character has its own "mind." Huge battles can be created more realistically, because each CG character can be allocated a "side," and will then react/fight accordingly, in a variety of different styles (depending on the circumstances they find themselves in), rather than having to create and program each CG character individually. In the very first "Massive" battle test at WETA, the battle was between "silver" and "gold" characters, the producers found characters on both sides at the back running away. Needless to say, they fixed the flaw in the program.