How to play an animation for a Non-Player Character with AnimationController from LocalScript?

To answer your question, you can't use LocalScript, you must use a server-side script,

The difference between a LocalScript and a server-side script is that local scripts can access client-only objects, for example a camera, server-side scripts can use the server, such as players.

First, you must know the LoadAnimation method, to use this method you must select a humanoid.

player = game:GetService("Players").LocalPlayer
wait(1)
animation = player.Character.Humanoid:LoadAnimation(animation location)
animation:Play()

To make a character animate on KeyDown

--My keydown deprecated script

player = game:GetService("Players").LocalPlayer
mouse = player:GetMouse()

mouse.KeyDown:connect(function(mouse)
    if key == "q" then
        local animation = player.Character.Humanoid:LoadAnimation(animation location)
        animation:Play()
    end
end)

--My keydown that is not deprecated script

--I'm new to do this.

function onKeyPress(inputObject, gameProcessedEvent)
    if inputObject.KeyCode == Enum.KeyCode.--put the key here then
        local animation = player.Character.Humanoid:LoadAnimation(animation location)
        animation:Play()
    end
end

game:GetService("UserInputService").InputBegan:connect(onKeyPress)

--Choose which one.

However, I can tell you something extra.

There is something called Motor6Ds, you can animate them if you would like to.

Link: http://wiki.roblox.com/index.php?title=API:Class/Motor6D

Some of these scripts were made in the text of scriptinghelpers, please give me the errors in developer console if it doesn't work, or goes wrong. If it goes wrong then do this line of code.

wait(animation time)
animation:Stop() 

~Sincerely CLVRB