What are the least powerful fictional artifacts, weapons or armour Goku could aquire to turn some of his losses into victories? Goku, as he was during fights where he loses 1v1 such as against Radditz, Great Ape Vegeta, Frieza (No Super Saiyan) and against Perfect Cell.

He is only allowed one item. Which ones would turn the tide in the most interesring way? Like obviously the infinity stones and gauntlet would help but that's too boring. 