I have been known to use the dreaded squirt bottle on my guys on occasion. Before I squirt them I will shake the botle so they here the sound of the water in the container and then I squirt them. After a few squirts I just have to shake the bottle and they will stop what ever they are doing (bad) at that moment.

I have been following the story of Mr. Magoo and I am sorry that you are having such a difficult time with him. But maybe it is time for a little "tough love", i.e. the squirt bottle...

Good luck!