Oofty Goofty’s Baseball Bat

Origin
Oofty Goofty was the stage name of Leonard ("Leon") Borchardt, a performer in California in the later 1800s. He traveled to San Francisco after his failed attempt as a ‘wild man’ act and his imprisonment for deserting the US Army. He tried various stints at breaking records and acting on stage, which both failed. He went into the business of a human punching bag, letting strangers kick him for 5 cents, cane him for 15 or hit him with his baseball bat for 25. He said he felt no pain during his beatings and did not cry out in pain. However, bare-knuckle boxer John L. Sullivan once beat him with a pool cue, breaking three vertebrae and reportedly giving him a permanent limp.

Effects
The bat makes a person unable to experience pain of any type. Over time, their back will become weaker and they will start to develop a limp.