Warning! Spoilers ahead for Justice League #59
In the latest issue of DC Comics' Justice League, the DC Universe's version of Marvel's vibranium has just made Hawkgirl the League's most valuable fighter. A new alien foe from another reality known as Brutus tried to claim the world as his own, but the Justice League quickly arrived to put a stop to his efforts. While the actions of several heroes such as Superman, Black Adam, and an impressive shark-based attack from Aquaman served to prove the League's power, it was actually Hawkgirl who motivated Brutus to retreat, and it's all thanks to Kendra Saunders' classic mace made from the legendary Nth metal.
In the DC Universe, Nth metal is an incredibly powerful alien metal with gravity negating properties. When forged into armor and weapons, Nth metal allows its wearers such as Hawkman and Hawkgirl to fly. However, it also grants increased strength, faster healing, and protection from extreme elements and temperatures. Not only that, but Nth metal has all kinds of unknown properties and powers that have barely begun to be tapped into, and it was heavily featured in Scott Snyder's and Greg Capullo's Dark Nights: Metal event. As such, Nth metal is not something to be underestimated in the DC Universe.
To Brutus' credit in Justice League #59 from writer Brian Michael Bendis and David Marquez, he seems smart enough to know that Hawkgirl and her Nth metal mace is not something to be messed with until he's better prepared. Furthermore, once his attention was focused on Kendra during the brawl, the mace itself had some sort of reaction to Brutus, much to their equal surprise along with the rest of the Justice League.
After this encounter, a bewildered Brutus escapes back to wherever he originally came from, though he did promise he would be back, better equipped to handle Hawkgirl and the rest of the League. Naturally, the team wants to know everything there is to know about Nth metal the moment the dust settles, as it's suddenly become their greatest asset. Batman hypothesizes that Brutus' power could be magically sourced, as they've seen Nth metal react to magic in different ways in the past, but Hawkgirl offers to reach out and see what the Thanagarian databases have to offer as well. Due to the fact that Nth metal was used in Dark Nights: Metal to bridge dimensional gaps, it's probable that it reacted to Brutus because he's likewise from another dimension.
In any case, Kendra's value on the team seems to have risen quite significantly when it comes to this new threat. Who knows what Brutus will bring with him whenever he does return, but hopefully Hawkgirl's mace and the help of the Justice League's expanding roster will be able to contend with whatever he ends up throwing at them. Nth metal is one of the most powerful metals and substances in the DC Universe, though it's equally mysterious. Here's hoping more details will come to light in future issues of Justice League from DC Comics.