Attempt to index local 'player'? I'm not sure to define the player in a regular function?

The error is on Line 16. "Attempt to index local 'player' (a nil value)" How would I define the player from a regular function. I tried putting the player in as a parameter but it didn't work.

Script in ServerScriptService Error on Line 16

leds = {}

function fade()
	for i, v in pairs(leds) do
		if v~= nil then
			v.Transparency = v.Transparency + 0.2
			if v.Transparency > 1 then
				v:Destroy()
			end
		end
	end
end


function makelig(player)
	local b = player.Character:GetChildren()
	for i = 1, #b do
	if b[i].Name == "Left Arm" or b[i].Name == "Left Leg" or b[i].Name == "Right Arm" or b[i].Name == "Right Leg" then	
	local tip = b[i]
	local lastpoint = b[i].Position
	local tool = b[i]
	if tip~= nil then
		local off = tip.Size.z/2
		local point = (tip.CFrame*CFrame.new(0, 0, -off)).p
		local unit = (lastpoint - point).unit
		local mag = (lastpoint - point).magnitude
		if tool.Parent.Humanoid.WalkSpeed > 55 and mag>10 then
			local middle = lastpoint-(unit*(mag/2))
			local cf = CFrame.new(middle, point)
			local l = Instance.new("Part")
			l.Shape = tip.Shape
			l.Name = "lightning"
			l.Anchored = true
			l.CanCollide = false
			l.Size = Vector3.new(0.2, 0.2, mag)
			l.BrickColor = BrickColor.new("Curry")
			l.Reflectance = tip.Reflectance
			l.Material = "Neon"
			l.TopSurface = 0
			l.Transparency = 0
			l.BottomSurface = 0
			l.Parent = tip
			l.CFrame = cf
			table.insert(leds, l)
			lastpoint = point
		end
		end
		end
	end
end





game.ReplicatedStorage.Lightning.OnServerEvent:Connect(function(player)
	game:GetService("StarterGui").ControlHUD.Frame.Plus.Lightning.Control:Clone().Parent = player.PlayerGui
	--player.PlayerGui:WaitForChild("ControlHUD").Frame.Plus.Lightning.Control:Clone().Parent = player.PlayerGui
		while true do
		makelig()
		wait()
		fade()
		wait()
	end
end)

LocalScript in TextButton

script.Parent.MouseButton1Down:Connect(function()
	game.ReplicatedStorage.Lightning:FireServer()
end)