Variable is nil, and I can't figure out why?

Using :FindFirstChild() does not always return something. Before calculating a path, check to see if prs exists.

if prs then
    -- Code for pathfinding
end

When you say that a variable is local, it only exists in the scope you define it. In other words, because you define local prs in the if block, prs does not exist outside of that if block! prs will never be a non-nil value. To fix this, specify that prs is local outside the if statement, in the same scope that you later use it: lua local prs if script.Parent.AttackingPlayer.Value ~= ("") then prs = game.Workspace:FindFirstChild(script.Parent.AttackingPlayer.Value) end SaltyIceberg is correct that you must also check to see if prs is non-nil.

Some other problems with this script: - return person() will fail, since person is not a function. Right after that, you have if person ~= nil then return person end, which makes the return person() redundant (in addition to being incorrect). Remove the else return person() part. - You have if searchforplayer() == nil then followed by while searchforplayer() == nil then, but you can just remove the if staement (along with the corresponding end) since while will not run its code even once if the condition is false - You should try to avoid running functions (especially ones that are complicated) more than necessary. You can save the result of calling searchforplayer() to a variable so you can access the player's name: lua if script.Parent.AttackingPlayer.Value == "" then print("Searching...") local player while true do player = searchforplayer() if player then break end wait(0.1) end script.Parent.AttackingPlayer.Value = player.Name script.Parent.Head["!Gui"].Frame.TextLabel.Visible = true script.Parent.Humanoid.JumpPower = 48 script.Parent.Humanoid.Jump = true wait(1) script.Parent.Head["!Gui"].Frame.TextLabel.Visible = false script.Parent.Humanoid.JumpPower = 0 end - if script.Parent.AttackingPlayer.Value ~= ("") then makes no sense because the code before it guarantees that AttackingPlayer will exist - range = math.huge could just be set once at the top of the script (where it currently says local range = 20) - You should assign AttackingPlayer to a local variable instead of saying script.Parent.AttackingPlayer every time - prs.HumanoidRootPart might not exist if the player (for instance) fell off the edge of the map; you should use FindFirstChild there - No point in having both prs and player both point to the player's character model (rename prs to player and remove the repetition) - When having the NPC follow the pathfinding result: - You don't want to use pairs, or else it'll attempt to follow the path out of order! - You don't have the script wait until the NPC actually gets to the checkpoint, you just tell it to start moving towards each checkpoint. You need to either have a loop where you wait until the NPC stops moving and/or gets close to its target.

Aside from the last point, I fixed the above in the following: ```lua local ts = game:GetService("TweenService") local event = Instance.new("BindableEvent") event.Name = ("StartAttacking") event.Parent = script.Parent.Parent

wait(5)

local attackingPlayer = script.Parent.AttackingPlayer
attackingPlayer.Value = ""

local range = math.huge

local function searchforplayer() local ray = Ray.new(script.Parent.HumanoidRootPart.CFrame.Position, script.Parent.HumanoidRootPart.CFrame.LookVector * 500) local hrp = script.Parent.HumanoidRootPart.Position local num = 8 local part = game.Workspace:FindPartOnRay(ray) local person = nil if part then if part.Parent:FindFirstChild("Humanoid") then if game.Players:FindFirstChild(part.Parent.Name) then print("Found player!") print(part.Parent.Name) person = part.Parent end end end if person == nil then local region = Region3.new(Vector3.new(hrp.X - num, hrp.Y - num, hrp.Z - num), Vector3.new(hrp.X + num, hrp.Y + num, hrp.Z + num)) local parts = game.Workspace:FindPartsInRegion3(region) for a, b in pairs(parts) do if b.Name == ("HumanoidRootPart") then print(b.Name) person = b.Parent end end end if person then return person end end

while true do if attackingPlayer.Value == "" then print("Searching...") local player while true do player = searchforplayer() if player then break end wait(0.1) end attackingPlayer.Value = player.Name script.Parent.Head["!Gui"].Frame.TextLabel.Visible = true script.Parent.Humanoid.JumpPower = 48 script.Parent.Humanoid.Jump = true wait(1) script.Parent.Head["!Gui"].Frame.TextLabel.Visible = false script.Parent.Humanoid.JumpPower = 0 end local path = game:GetService("PathfindingService"):CreatePath() local player = game.Workspace:FindFirstChild(attackingPlayer.Value) event:Fire(attackingPlayer.Value) local playerHRP = prs:FindFirstChild("HumanoidRootPart") if playerHRP then path:ComputeAsync(script.Parent.HumanoidRootPart.Position, playerHRP.Position) local points = path:GetWaypoints() script.Parent.Parent.Points:ClearAllChildren() for a, b in pairs(points) do part = Instance.new("Part") part.CanCollide = false part.Size = Vector3.new(1,1,1) part.Position = b.Position part.Anchored = true part.Transparency = 1 part.Parent = script.Parent.Parent.Points end if path.Status == Enum.PathStatus.Success then for a, b in ipairs(points) do script.Parent.Humanoid:MoveTo(part.Position) if b.Action == Enum.PathWaypointAction.Jump then script.Parent.Humanoid.Jump = true end end end end end ```