why are my tools not killing people when FE is on?

In the past, when I had FE disabled, the tools worked just fine. But now, ever since FE is forced, the tools would kill the player on one players screen, but on the player that is dying, they are still alive. Does anyone know why?

THIS IS A LOCALSCRIPT IN ONE OF THE TOOLS

------------------------
--[[UTIL Functions]]--
------------------------
--Global functions used by all classes are wrapped in UTIL
--deal with it.
local UTIL = {}
 
function UTIL.Class(tableIn,template)
        tableIn = tableIn or {}
        local mt = {
        __metatable = UTIL.DeepCopy(template);
        __index     = UTIL.DeepCopy(template);
        }
        return setmetatable(tableIn, mt)
end
function UTIL.MakeClass(...)
        local arg = {...}
        assert(#arg>0, 'ERROR: class needs 1 argument or more')
        local members = arg[1]
        for i=2,#arg,1 do
                if type(arg[i])=='table' then
                        for key,val in pairs(arg[i]) do
                                if not members[key] then
                                        members[key] = val
                                end
                        end
                end
        end
        local function New(init)
                return UTIL.Class(init or {},members)
        end
        local function Copy(obj, ...)
                local newobj = obj:New(unpack(arg))
                for n,v in pairs(obj) do newobj[n] = v end
                return newobj
        end
        members.New  = New
        members.Copy = Copy
        return mt
end
 
function UTIL.DeepCopy(orig)
    local orig_type = type(orig)
    local copy
    if orig_type == 'table' then
        copy = {}
        for orig_key, orig_value in next, orig, nil do
            copy[UTIL.DeepCopy(orig_key)] = UTIL.DeepCopy(orig_value)
        end
        setmetatable(copy, UTIL.DeepCopy(getmetatable(orig)))
    else -- number, string, boolean, etc
        copy = orig
    end
    return copy
end

function UTIL.Instantiate(guiType)
	return function(data)
		local obj = Instance.new(guiType)
		for k, v in pairs(data) do
			if type(k) == 'number' then
				v.Parent = obj
			else
				obj[k] = v
			end
		end
		return obj
	end
end 

function UTIL.RetroRegister(func,...)
	func()
	for _,i in ipairs({...}) do
		i:connect(func)
	end
end

-- Waits for a new character to be added if the current one is invalid
-- (Ensures that you don't have the old dead character after a respawn)
function UTIL.WaitForValidCharacter(player)
	local character = player.Character
	if not character or not character.Parent or not character:FindFirstChild('Humanoid') or character.Humanoid.Health <= 0 then
		player.CharacterAdded:wait()
		wait(0) --NOTE: Necessary for server scripts executing on the same event
		character = player.Character
	end
	return character
end


-- Returns a character ancestor and its Humanoid, or nil
function UTIL.FindCharacterAncestor(subject)
	if subject and subject ~= Workspace then
		local humanoid = subject:FindFirstChild('Humanoid')
		if humanoid then
			return subject, humanoid
		else
			return UTIL.FindCharacterAncestor(subject.Parent)
		end
	end
	return nil
end

UTIL.AssetURL = 'http://www.roblox.com/asset/?id='


UTIL.TouchEnabled = game:GetService("UserInputService").TouchEnabled 
do
	local suceeded,_ =pcall(function() game.Workspace.CurrentCamera:GetPanSpeed() end)
	UTIL.CanCheckPanSpeed = suceeded
end


local DebrisService = Game:GetService('Debris')
local DebugPrintOffset = 0
function UTIL.Dprint(...)
	local line = ''
	for _, segment in pairs({...}) do
		line = line .. (line and ' ' or '') .. tostring(segment)
	end
	local gui = Instance.new('ScreenGui')
	local label = Instance.new('TextLabel')
	label.Text = line
	label.Size = UDim2.new(0.25, 0, 0.05, 0)
	label.BackgroundTransparency = 0.5
	label.Position = UDim2.new(0, 0, 0, DebugPrintOffset)
	label.TextWrapped = true
	label.Parent = gui
	DebrisService:AddItem(gui, 30)
	gui.Parent = script.Parent
	DebugPrintOffset = (DebugPrintOffset <= 600) and DebugPrintOffset + 30 or 0
end
--
--All Welding Related Utility functions should be put here
--
WeldUtil = {}


do


	function WeldUtil.WeldBetween(a, b)
		local weld = Instance.new("Weld")
		weld.Part0 = a
		weld.Part1 = b
		weld.C0 = CFrame.new()
		weld.C1 = b.CFrame:inverse() * a.CFrame

		weld.Parent = a
		return weld
	end
	
	function WeldUtil:PermaWeld(weld)
		local OriginalParent = weld.Parent
		weld.Changed:connect(function()
			Delay(0,function() weld.Parent = OriginalParent end)
		end)
	end

end

local InternalEvent =
{
	Listeners = nil,
}
do
	UTIL.MakeClass(InternalEvent)
	function InternalEvent:Connect(func)
		if not self.Listeners then self.Listeners = {} end
		table.insert(self.Listeners,func)
	end
	function InternalEvent:Fire(...)
		if not self.Listeners then return end
		local args = {...}
		for _,i in ipairs(self.Listeners) do
			Spawn(function() i(unpack(args)) end)
		end
	end
end

--[[Sword Part Class]]--
	
local SwordPart =
{
	Damage = 20,
	AttackTime = 1,
	CoolDown = 0.1,
	
	LastSwing = 0,
	LastHit = 0,

	Part= nil,
	Owner = nil,--player object that owns this sword
	
	OnHit = nil,
	OnHitHumanoid = nil,
	OnAttackReady = nil,
	OnAttack = nil,
	
	
	SwingSound = nil,
	HitSound = nil,
	SwingAnimation = nil, --animation track!
	
	ActiveConnections = {},
	
}
do
	UTIL.MakeClass(SwordPart)
	function SwordPart.New(npart,nowner)
		local init= UTIL.DeepCopy(SwordPart)
		init.Part= npart
		init.Owner = nowner
		table.insert(init.ActiveConnections,init.Part.Touched:connect(function(hit) init:SwordTouch(hit) end))
		
		init.OnHit = InternalEvent.New()
		init.OnHitHumanoid = InternalEvent.New()
		init.OnAttackReady = InternalEvent.New()
		init.OnAttack = InternalEvent.New()
		
		return init
	end
	
	function SwordPart:SwordTouch(hit)
		if tick()-self.LastSwing >self.AttackTime or tick()-self.LastHit<self.AttackTime then return end
		self.OnHit:Fire(hit)
		local character,humanoid = UTIL.FindCharacterAncestor(hit)
		if character and character ~= self.Owner.Character then
			humanoid:TakeDamage(self.Damage)
			self.OnHitHumanoid:Fire(humanoid,hit)
			self.LastHit = tick()
			if self.HitSound then
				self.HitSound:Play()
			end
		end
		
	end
	
	function SwordPart:DoSwing()
		if tick()-self.LastSwing<self.AttackTime+self.CoolDown then
			return
		end
		
		if self.SwingAnimation then
			self.SwingAnimation:Play()
		end
		if self.SwingSound then
			self.SwingSound:Play()
		end
		self.LastSwing = tick()
		self.OnAttack:Fire()
	end
	
	function SwordPart:Destroy()
		for _,i in pairs(self.ActiveConnections) do
			i:disconnect()
		end
	end
end
do
	local Handle = script.Parent
	local Tool = Handle.Parent
	
	local Player = game.Players.LocalPlayer
	local Character = UTIL.WaitForValidCharacter(Player)
	local SwingAni = UTIL.Instantiate"Animation"
	{AnimationId = "http://www.roblox.com/Asset?ID=74894663"}
	
	local HitSound = Handle:WaitForChild('Hit')
	local SwingSound = Handle:WaitForChild('Swing')
	
	local SwingAniTrack
	
	local Sword
	
	
	Tool.Equipped:connect(function(mouse)
		Sword = SwordPart.New(Handle,Player)
		Sword.Damage = 25
		Sword.HitSound = HitSound
		Sword.SwingSound = SwingSound
		Character = UTIL.WaitForValidCharacter(Player)
		local Humanoid = Character:FindFirstChild('Humanoid')

		SwingAniTrack = Humanoid:LoadAnimation(SwingAni)
		Sword.SwingAnimation = SwingAniTrack
		
		Sword.OnHitHumanoid:Connect(function(humanoid,hit)
			local myTorso = Character:FindFirstChild('Torso')
			local torso = humanoid.Parent:FindFirstChild('Torso')
		if not torso or not myTorso then return end end)
		
		mouse.Button1Down:connect(function()
			Sword:DoSwing()
		end)
	end)
	Tool.Unequipped:connect(function()
		Sword:Destroy()
	end)

end