Hooray! The unity team accepted my submission to the store now that I have my website set up correctly.
You can see the demo scene that I've been using for my videos, it comes complete with 3 prefabs (one for each character) as well as 2 additional prefabs for the projectiles. The SpriteCharacterController class shows you an example of how to control and animate the characters. It includes basic input for movement, jumping, casting and attacking. It also has a basic health system in place so that you can damage the characters (which will play the hurt animation) and then if their health drops to zero, they will die.
It should give you a nice starting point for developing a fuller interaction class as part of a game of your own design.