Bruce's new fascination and training consisted of the outdated weapon. Instead of smaller more practical weapons like knives.   When you inquired about him wanting one, and why he chose it he responded with-

After his flippant response you left me alone..  Even when he started researching materials, how to sharpen blades. But the next time you saw him in a fight he brought out two retractable bo staffs made by Lucius.  Fighting a gang on his own. 

He swung them snapping bone or slashing through clothes and body armor.

Knocking someone down only to slam the end of it into their chest again and again. Impaling someone through a wall before yanking it out and turning away. Collapsing and pocketing both before he turned to you." Still think they were a poor choice of weaponry?" 

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