monster.Humanoid.HealthChanged:Connect(function(Health)
if Health <= 200000 then
local forcefield = Instance.new("ForceField")
forcefield.Parent = monster
forcefield.Visible = true
wait(6)
forcefield:Destroy()
end
end)
Just disconnect the connection after the condition is fufilled.
local HealthChangedConnection = nil :: RBXScriptConnection?
HealthChangedConnection = monster.Humanoid.HealthChanged:Connect(function(Health)
if Health <= 200000 then
local forcefield = Instance.new("ForceField")
forcefield.Parent = monster
forcefield.Visible = true
wait(6)
forcefield:Destroy()
HealthChangedConnection:Disconnect()
end
end)