Not super sure this is a bug, but the brick wand has the weapon tag, despite dealing no damage naturally.
With no damage on the base item rage won't affect it, but any outside source of damage that works on weapons (gems, copper chest, etc) will give it a base damage, and allow rage to work with it.

This made a run with it and egg timer very easy. a couple other structures with haste and the egg timer, and filled the inventory with manastones. The sheer ease of setting up this build makes this probably the best common item in the game.