Yajirobe

I’ll probably do Vegeta, Nappa and Saibaman next

My man had the same upbringing as Goku minus the training from Gohan and was just as strong as him after a bunch of extra training. Goku even states "He's the toughest guy i've ever met!" As Tien was equal in power level to Goku that means that Yajirobe may have been even stronger than Goku. And that was without any training. The only explanation is that Yajirobe has a better growth rate. This is proven in that his power level was 920 after only training once(Saiyan arc). He even cut Oozaru Vegeta's tail and as Nappa had toughened his tail Vegeta likely had as well. This means that Yajirobe can cut people who are "more powerful" than he is. In the Buu arc Vegeta states that Goku is more talented than him and Yajirobe was more talented than Goku. This means that Yajirobe's overall growth rate is greater than Goku or Vegeta and this also means he has greater potential. If he ever unlocked it he would be unstoppable. Tldr; Yajirobe is busted.