To create a 50,000-strong mob of intelligent digital warriors, Massive creator Stephen Regelous builds each agent piece by piece, implanting a digital brain into a rendered body. Then he replicates and tweaks the agents. In a scene, agents make decisions based on their abilities-and on what's happening around them.

2 INSET MOTION
Movement data gleaned from human actors performing in a motion-capture studio is loaded into the Massive program and associated with a skeleton. The programmer can fine-tune the agents' movements using the controls on the bottom of the screen.

3 CREATE THE BRAIN
The core of every agent is its brain, a network of thousands of interconnected logic nodes (only a fraction of which are shown here). One group of nodes might represent balance, another the ability to tell friend from foe. The agent's brain relies on fuzzy logic, a kind of artificial intelligence in which values are continuously variable and outcomes intuitive. Massive characters act more like people than like robots.
4 REPLICATE
When a variety of agents have been developed, copies are created from each blueprint, then the copies are tweaked to give each fighter a unique mix of various characteristics-height, aggressiveness, even dirtiness. The 50,000 characters in the scene will act as individuals. They are placed into a battlefield grid for testing.
5 ATTACK
The simulations begin. Since agents are programmed with tendencies, not specific tasks to accomplish, there is no
guarantee they will behave as the director needs them to. Only through a trial-and-error process, in which the characters' programs are constantly adjusted, is the battle scene finalized.
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