Runs function constantly?

I'm trying to take all the zombies off when the character dies and resets the level, but instead of spawning 3 zombies for level 1, it spawns an uncountable amount.

Zombie = game.Lighting.Zombie:Clone()
Num_Zom = 0
Level = 1

function Stance()
	repeat local Zom2 = Zombie:Clone()
	local pos = Vector3.new(math.random(-150,150),0,math.random(-150,150))
	Zom2.Parent = workspace
	Zom2:MakeJoints()
	Zom2:MoveTo(pos)
	Num_Zom = Num_Zom + 1
	until Num_Zom == Level * 3
	while wait(3) do
	for i,v in pairs (game.Workspace:GetChildren()) do
	if v.Name == "Zombie" and v.Humanoid.Health == 0 then
	Num_Zom = Num_Zom - 1
	v:remove()
	end
	if Num_Zom == 0 then
	Level = Level + 1
	for i,v in pairs (game.Players:GetPlayers()) do
		v.stats.Level.Value = Level
	end
	Stance ()
	end
	end
	end
end

game.Players.PlayerAdded:connect(function(Player)
	Stance()
end)

game.Players.PlayerAdded:connect(function(Player)
local ting = false
Player.CharacterAdded:connect(function(Char)
if ting == true then
	ting = false
	Stance()
end
Char.Humanoid.Died:connect(function()
	for i,v in pairs (game.Workspace:GetChildren()) do
	if v.Name == "Zombie" then v:remove()
	Level = 1
	end
	end
ting = true
end)
end)
end)

while wait(5) do print (Level) end