Dragon Ball Super's Galactic Patrol Prisoner arc continues with the latest chapter of the manga, and it continues make huge reveals about the multiverse. One of the more interesting additions to the arc was the mysteriously strong Merus. This Galactic Patrol member surprisingly defeated Goku and Vegeta at their first meeting, and had been fighting against Goku on equal footing. So fans were left wondering what exactly what his deal was. But in Chapter 55, Merus is revealed to actually be an Angel in training...but also an Angel who was dangerously close to breaking the mysterious Angel laws.
Chapter 55 of the series caps off the intense training between Merus and Goku, but before Merus decided to go all out on Goku, Whis suddenly arrives and puts a stop to things to keep Merus from breaking the Angel laws and being erased from existence.
Whis confirms that training is alright -- which would explain why Whis was able to train Goku and Vegeta from before -- but Merus was close to breaking the laws because he was preparing to go all out against Goku. This would have been considered a battle between the two, and fighting is completely against their laws.
Whis reveals that the harsh punishment for breaking one of these laws is total eradication without a trace. Angels can't die, but this is one of the only ways Angels can be wiped out from existence. Whis also mentions how this is an absolute truth for the Angels, and is just part of the nature for the Angels' existence. So while it seems like Angels can have their own identities, desires, and personalities, their are limits to what they can do.
It's why the angels have been seen as a bystander existence that don't really interact in any major way. Whis has trained Goku and Vegeta, and even distracted Broly for a moment, but he's never actually done any major damage. Perhaps this is the tease of the kind of abilities they have that a law is necessary to keep them from actually wreaking havoc in the multiverse.
The Japanese-language and English dub releases of Dragon Ball Super are now complete and available to stream with FunimationNOW and Crunchyroll. Viz Media is releasing new chapters of the manga at a monthly rate that can be read entirely for free through the Shonen Jump digital library, and Dragon Ball Super's big movie, Dragon Ball Super: Broly, is now available on Blu-ray and DVD. Fans in Japan are also able to enjoy fresh non-canon adventures from the franchise with new episodes of Super Dragon Ball Heroes' promotional anime series.