[@Blueflame] I know you feel bad for god-modding but the actual 'intention' of your characters action has given something for us all to mention and work with so thanks :)

Live and learn.

Your plan was fine just have to state that you wait for the creature to swing at you so you can 'try' do your plan.
That way you let him know your intentions but you haven't assumed any of the creatures actions. 
If he likes it he might set it up, if he doesn't then something else will happen.