How can I rewrite this dagger-throwing script to be working in FE again?

Hey guys, I got a script here that should equip you with a knife with an aiming laser that only the wearer can see. that knive you can throw at someone to kill him/destroy his shield-aura. The script is pretty big imo and i got no idea to convert all of that so it works again.

wait(0.6)
local player = game.Players.LocalPlayer
local character = player.Character
local pgui = player.PlayerGui
local torso = character.Torso
local gamemodel = Workspace.GameModel

local pmouse = player:GetMouse()
local camera = Workspace.CurrentCamera

local tool = script.Parent
local daggerspeed = 120
local spinspeed = 2
local maxdistance = 300
local fadetm = 1

local r_serv = game:GetService("RunService")

local fr = script.shadowdg:clone()
fr.Frame.Visible = true
local reach = fr.Frame.reach
reach.Text = ""


local beam = Instance.new("Part")
beam.Name = "DaggerBeam"
beam.formFactor = "Custom"
beam.Size = Vector3.new(0.2, 0.2, 0.2)
beam.Transparency = 0.2
beam.CanCollide = false
beam.Anchored = true
beam.TopSurface = 0
beam.BottomSurface = 0
beam.BrickColor = BrickColor.new("Really red")
local m = Instance.new("BlockMesh")
m.Scale = Vector3.new(1, 1, maxdistance / 0.2)
m.Offset = Vector3.new(0, 0, -maxdistance / 2)
m.Parent = beam

if _G.MOBILE_DEVICE then
    fr.Frame.reach.Visible = false
    fr.Frame.horizontal.Visible = false
    fr.Frame.Size = UDim2.new(0, 120, 0, 120)
    fr.Frame.Position = UDim2.new(1, -130, 0.5, -60)
    beam.Transparency = 1
end

function GenIgnore()
    local result = {}
    local ch = game.Players:GetPlayers()
    for i = 1, #ch do
        local char = ch[i].Character
        if char ~= nil then
            local sc = char:GetChildren()
            for a = 1, #sc do
                if sc[a]:IsA("Hat") or sc[a]:IsA("Tool") then
                    result[#result + 1] = sc[a]
                end
            end
        end
    end
    return result
end

function randomsound()
    local rnd = {"146594648", "146594640", "146457047"}
    return "http://www.roblox.com/asset/?id=" .. rnd[math.random(1, #rnd)]
end

function RayCast(ps1, ps2, ignore)
    local ray = Ray.new(
        ps1,
        (ps2 - ps1).unit * (ps1 - ps2).magnitude
    )
    local nign = ignore
    nign[#nign + 1] = character
    return Workspace:FindPartOnRayWithIgnoreList(ray, nign) --hit, position
end

    local dg = Instance.new("Part")
    dg.formFactor = "Custom"
    dg.Size = Vector3.new(0.2, 0.2, 0.2)
    dg.BrickColor = BrickColor.new("Really black")
    dg.Transparency = 0.2
    dg.Anchored = true
    dg.CanCollide = false
    dg.TopSurface = 0
    dg.BottomSurface = 0
    local m = Instance.new("SpecialMesh")
    m.MeshId = "http://www.roblox.com/asset/?id=20719463"
    m.Scale = Vector3.new(1, 1.4, 1)
    m.Parent = dg
    local loop = Instance.new("Sound")
    loop.SoundId = "http://www.roblox.com/asset/?id=146470466"
    loop.Volume = 1
    loop.Looped = true
    loop.Parent = dg

    local dagger_rot = CFrame.Angles(math.rad(-90), math.rad(0), math.rad(-90))
    local spin = CFrame.Angles(0, 0, 0)

function DaggerScript(ps)
    local tps = torso.Position
    script.Parent = pgui
    tool.Parent = nil
    --DAGGER SCRIPT

    local ignores = GenIgnore()
    ignores[#ignores + 1] = gamemodel
    local tcf = CFrame.new(tps, ps)
    local travelled = 0
    dg.Parent = gamemodel
    dg.CFrame = tcf * dagger_rot * spin

    coroutine.resume(coroutine.create(function()
        wait(0.1)
        loop:play()
    end))

    while true do
        local st = tick()
        r_serv.RenderStepped:wait()
        local delta = (tick() - st)
        local dist = daggerspeed * delta
        local nps = tcf * CFrame.new(0, 0, -dist)
        spin = spin * CFrame.Angles(0, math.rad(-360 * delta * spinspeed), 0)
        travelled = travelled + dist

        --STUFF
        while true do
            local hit, pos = RayCast(tcf.p, nps.p, ignores)
            if hit ~= nil then
                local hum = hit.Parent:findFirstChild("Humanoid")
                if hum == nil then
                    hum = hit.Parent.Parent:findFirstChild("Humanoid")
                end
                if hum ~= nil then
                    ignores[#ignores + 1] = hum.Parent
                    local sdf = hum.Parent:findFirstChild("ShieldDefence")
                    if sdf ~= nil then
                        sdf.TakeDamage.Value = true
                    else
                        hum.Parent:BreakJoints()
                        local sndp = Instance.new("Part")
                        sndp.formFactor = "Custom"
                        sndp.Size = Vector3.new(0.2, 0.2, 0.2)
                        sndp.Transparency = 1
                        sndp.Anchored = true
                        sndp.CanCollide = false
                        sndp.CFrame = CFrame.new(pos)
                        sndp.Parent = gamemodel
                        local snd = Instance.new("Sound")
                        snd.Volume = 1
                        snd.SoundId = randomsound()
                        snd.Parent = sndp
                        coroutine.resume(coroutine.create(function()
                            wait(0.1)
                            snd:play()
                            wait(1)
                            sndp:remove()
                        end))
                    end
                else
                    ignores[#ignores + 1] = hit
                end
            else
                break
            end
        end
        --STUFF

        tcf = nps
        dg.CFrame = tcf * dagger_rot * spin
        if travelled >= maxdistance then
            break
        end
    end

    local ld = 0
    while ld ~= 1 do
        local st = tick()
        r_serv.RenderStepped:wait()
        local delta = (tick() - st)
        ld = math.min(1, ld + delta / fadetm)
        local dist = daggerspeed * delta
        dg.Transparency = 0.2 + (0.8 * ld)
        spin = spin * CFrame.Angles(0, math.rad(-360 * delta * spinspeed), 0)
        tcf = tcf * CFrame.new(0, 0, -dist)
        dg.CFrame = tcf * dagger_rot * spin
    end

    dg:remove()

    --DAGGER SCRIPT
    print("The end")
    script.Parent = nil
end

local throwmode = false

local bounce = false
local eq = false
tool.Selected:connect(function(mouse)
    eq = true
    if bounce then return end
    fr.Parent = pgui
    beam.Parent = camera
    mouse.Button1Down:connect(function()
        fr.Parent = nil
        beam.Parent = nil
        if bounce then return end
        bounce = true
        if not throwmode then
            DaggerScript(mouse.Hit.p)
        else
            local ps = mouse.Hit.p
            DaggerScript(Vector3.new(ps.x, torso.Position.y, ps.z))
        end
    end)
    mouse.KeyDown:connect(function(key)
        if string.lower(key) == "q" then
            throwmode = not throwmode
        end
    end)
end)

tool.Deselected:connect(function()
    eq = false
    fr.Parent = nil
    beam.Parent = nil
end)

while not bounce do
    r_serv.RenderStepped:wait()
    if eq then
        if not throwmode then
            beam.CFrame = CFrame.new(torso.Position, pmouse.Hit.p)
            if (torso.Position - pmouse.Hit.p).magnitude <= maxdistance then
                reach.Text = "WILL REACH TARGET"
                reach.TextColor3 = Color3.new(0, 1, 0)
            else
                reach.Text = "WON'T REACH TARGET"
                reach.TextColor3 = Color3.new(1, 0, 0)
            end
        else
            local ps = pmouse.Hit.p
            beam.CFrame = CFrame.new(torso.Position, Vector3.new(ps.x, torso.Position.y, ps.z))
            if (torso.Position - Vector3.new(ps.x, torso.Position.y, ps.z)).magnitude <= maxdistance then
                reach.Text = "WILL REACH TARGET"
                reach.TextColor3 = Color3.new(0, 1, 0)
            else
                reach.Text = "WON'T REACH TARGET"
                reach.TextColor3 = Color3.new(1, 0, 0)
            end
        end
    end
end
beam.Parent = nil

Sry for the script being so damn long, but i really dont know which parts to edit and which not. :/