What's the problem?

• Body Colors has a space in between
• LocalScripts run before the server start, therefore the script runs before the character loads
• Why would you be using a local script to change parts especially if other players will see it, if FE is on then the player's Body Colors will not be visible to other players

What can I do?

Locate Body Colors like so: Character["Body Color"] or use :FindFirstChild() or even better: :WaitForChild().

Character["Body Color"]
Character:FindFirstChild("Body Color")
Character:WaitForChild("Body Color")

You can also stop using LocalScripts all together, because in this situation, it'll be easier to use a server Script.

What are the Differences between Server-Sided and Client-Sided

ServerSided: * Runs after the server is loaded * Can affect only server-sided actions * Can affect other players ClientSided: * Runs as soon as possible * Only affects the Player * Only runs if inside of a Descendant of Player

What's the Difference between the 3 ways of calling Objects through strings?

["Body Color"] is the same as calling something like so: Character.BodyColor. If it doesn't exist, the script will error and the script will stop itself there. :FindFirstChild() is the same but will return nil if it doesn't exist and will still run the rest of the code. :WaitForChild() is the same as above, but will Yield the script(even though it's technically a regular function) for 5 seconds and will return nil if the object doesn't exist for 5 seconds. Note it has a 2nd parameter than can change how long the function will yield.

Final Product

game:GetService("Players").PlayerAdded:connect(function(plyr)
    plyr.CharcterAdded:connect(function(char)
        repeat wait() until char:FindFirstChild("Body Color") --This way we don't need to worry about the 5 second time limit because each computer is different.
        local hulkcolor = char:FindFirstChild("Body Color")
        hulkcolor.HeadColor = "Sea green"
        hulkcolor.LeftArmColor = "Sea green"
        hulkcolor.RightArmColor = "Sea green"
        hulkcolor.RightLegColor = "Bright violet"
        hulkcolor.LeftLegColor = "Bright violet"
        hulkcolor.TorsoColor = "Sea green"
    end)
end)

Hope it helps!