A behavior plug-in is used with the 3ds Max character studio crowd system to simulate crowd activities. Behavior plug-ins typically derive from the class BaseBehavior.
The Formation behavior lets you specify a formation for a selection of delegates, and will then try to keep the delegates in that formation while the delegates move.
The Pursuit behavior lets you specify an object as a target for delegates to pursue. It is similar to the Seek behavior in this respect. However, the delegates, instead of seeking the target at its current position, they will seek a position ahead of the target, based upon the target's speed and it's distance from the delegate.