Weapon Lagging when sp

I recently made a script that spawns Zombies when the folder has x amount of zombies left, it repeats and Im seeing server lag, is there any way I can fix this with it still looping?

while true do

local Spawns = workspace:WaitForChild("World").Objects:WaitForChild("Map").Locations:GetChildren()
local NPC = replicatedStorage:WaitForChild("Assets").Zombies:GetChildren()
local rand = math.random(1,#NPC)

if game.ReplicatedStorage.Match.Value == true then
	local children = workspace:WaitForChild("World").Objects:WaitForChild("Map").Zombies:GetChildren()
	local loco = game.Workspace:WaitForChild("World").Objects:WaitForChild("Map").Zombies
	local count = #children
	if count < 6 then
		local NPCs = NPC[rand]:Clone()
		NPCs.Parent = loco
	print("Cannot spawn, match isn't ready")


From what I can see, I don’t really understand why the server is lagging (assuming the lag you are referring to is not from a Script Timeout error). Perhaps the lag is occurring over time from memory build-up and/or memory leakage.

However, you don’t necessarily have to be constantly checking for a decrease in the count of zombies. Instead, you can connect an event to fire when a child (zombie) is removed from the folder.

    -- Continue from here

This event will use less memory than constantly checking with a while loop, and hence, reduced server lag over time, but it will also allow you to disregard the check for when the value of Match is true as you can simply connect the event when needed. Remember to disconnect the event when you no longer need it, to prevent memory leakage (arguably one of the main ways server lag builds-up).

So I tested this, it only spawns one of them at a time, and if I do more it lags (How could I spawn multiple with this?)