Developing an NPC Animator Controller

The FSM must be complemented by a Mecanim animator graph, as each state involves a unique animation and each one should play at the appropriate time. You create a new animator asset simply by right-clicking inside the Projectpanel and choosing Create | Animator Controller from the context menu; name this controllerEnemy.

Ensure that you add this as an Animator component to the zombie in the scene by dragging and dropping the asset from the Project panel to the mesh in the SceneViewport:

Creating a new Animator Controller for the zombie NPC

First, create a new animator integer parameter and name it AnimState. This parameter represents the currently active state of the zombie in the graph. Its values will exactly match the value of the AIState enum, coded for the AIEnemy class: 0 = Idle, 1 = Chase, 2 = Attack, and 3 = Dead:

Creating a new Animator Controller for the zombie NPC

Now for the starting state, create a new Empty state by right-clicking in the graph...