How do you make a character die?

I can see you don't know enough about unity to be making such a complex thing, but I think a good aproach would be following some tutorials (walkerboystudio.com helped me a lot) and read about "prefabs" and about "Instantiate". You could destroy your character gameObject and then instantiate the dead character prefab. This is only a way, there are thousandsm so you better start watching tutorials and in a few time everything will be clearer.

hi, you can use

animation.Play("die animation");

where "die animation" is the name of your animation.OK.

still you confused refer this, http://docs.unity3d.com/Documentation/ScriptReference/Animation.Play.html