local Players = game:GetService("Players")

local function onCharacterAdded(character)
    local humanoid = character:WaitForChild("Humanoid")

    humanoid.MaxHealth = math.huge
    humanoid.HealthChanged:Connect(function(newHealth)
        if humanoid.Health > 0 then
            humanoid.Health = humanoid.MaxHealth
        end
    end)
end

local function onPlayerAdded(player)
   player.CharacterAdded:Connect(onCharacterAdded)
end

Players.PlayerAdded:Connect(onPlayerAdded)