Dragon Ball Super is in the climactic battle of its "Galactic Patrol Prisoner" manga arc, as Goku battles Planet-Eater Moro using the new power of Perfected Ultra Instinct. After Goku thrashes Moro, he spends some time in the latest chapter trying to get to know his opponent a little better - before possibly having to destroy him. In the process of Moro accepting help (only to pull a major triple-cross), Goku gets some key answers about Moro's life and his past. One of the bigger topics that Goku seems interested in is Moro's fight technique - and why he never trained to hone it.
Warning: Dragon Ball Super manga chapter 65 SPOILERS Follow!
The first attempt Goku makes to reform Moro is giving the gravely injured villain a Senzu bean, in order to restore his health and power. Goku offers that olive branch with the caveat that Moro needs to surrender himself to the Galactic Patrol and return to prison; instead, Moro tries to once again punch a hole through Goku's chest!
Unfortunately for Moro, part of Perfected Ultra Instinct's new power is the body's ability to autonomously defend itself; Moro's blow lands on an impenetrable chest and promptly breaks. With the villain writhing in pain, Goku feels it is an opportune time to talk about the need and benefit of proper training:
"Have you ever trained?" Goku asks Moro. "You might've wound up even stronger if you'd just trained instead of eating planets and stealing lives. That's a real shame, cuz I never came across anyone as tough as you. If you were a decent guy, I'd love to fight again after you'd gone through some training."
Of course, Moro has no interest in training to be a better fighter - or a better person. Instead, he finds a way to hijack Ultra Instinct for himself and tries to use it to annihilate Goku and Earth. In the end, Goku's little getting-to-know-you discussion backfires big-time: Moro fuses with Earth and is now a ticking bomb of energy that will either destroy the planet - or the entire galaxy.
The fact that Moro isn't a trained fighter was one of the more interesting aspects of the villain. Moro had natural fight abilities, but the true threat is his magical abilities, which include siphoning life and energy from opponents like a vampire, and being able to magically weaponize the energy of a planet's molten core, and other such techniques. However, as we've come into the final stretch of this arc Moro has settled into a more traditional Dragon Ball Z villain mold, absorbing and/or fusing to gain new forms and powers, like Cell or Majin Buu.
In the end, Dragon Ball fans have been interested to see if Moro takes on another, larger role in the series (like a God of Destruction), but so far, it's looking like he'll be a one-and-done...