What's an efficient way to make an NPC face your character?

I'm currently doing this, which works fine;

while true do
	wait()
	local plr = playerValue.Value
	if plr then
		local direction = (plr.Character.Torso.Position - bot.Torso.Position) * Vector3.new(1, 0, 1)
		bot.Torso.CFrame = CFrame.new(bot.Torso.Position,bot.Torso.Position + direction)
	end
end

with playerValue being an ObjectValue equal to the correct player.

However, with lots of NPCs this causes lots of lag. The Script Performance window shows that this is very inefficient, on a large scale at least.

Do you know any more efficient method of making the bot face your character?

You could use the changed method:

playerValue.Value.Character.Torso.Changed:connect(function(property)
if string.lower(property) == "position" then
local direction = (playerValue.Value.Character.Torso.Position - bot.Torso.Position)
bot.Torso.CFrame = CFrame.new(bot.Torso.Position,bot.Torso.Position + direction)
end
end)

I'm not sure if this would be considered more efficient, but it wouldn't cause lag if the player isn't moving.