He likes to defend and protect.
His most recent weapon that actually works and is fairly accurate is this popsicle slingshot.
he has learned that shooting it toward me is a good way to garner a yelled: HEY! Watch it buddy! We don't shoot people remember??? Get the bad guys NOT mom!
He doesn't like the yells, so his aim is drastically improving.
While I'm on the subject may I recommend UBER-stix. It's a very helpful device for the builders among us. You can use most anything you have to build with. The cutter works great and is safe for children to use.