WARNING: The following contains spoilers for Dark Ages #3, on sale now from Marvel Comics.
For years, the Invisible Woman has not so quietly been the most powerful member of the Fantastic Four. Over the years, her initial powers of invisibility have been expanded to include incredibly potent shields powerful enough to suppress massive explosions and even repelling telepathy.
There have been many instances of her utilizing her powers to contain blasts of intense magnitude, with her latest showing being one of the most impressive to date. In Dark Ages #3 (by Tom Taylor, Iban Coello, Brian Reber, and VC's Joe Sabino), the Invisible Woman is able to contain a dying Johnny Storm's final outburst of energy... and not be harmed at all.
In the world of Dark Ages, Susan Richards has suffered the loss of most of her family. Ben Grimm fell in the battle to defeat the Unmaker, reduced to rubble by a massive blast of energy. In the years since, her husband and son have gone missing as well, with Reed Richards seemingly forced to work alongside Apocalypse. In an effort to locate a recently kidnapped Tony Stark, the remaining heroes send Quicksilver to investigate. When the speedster returns, he's been turned into a living weapon by the Purple Man, which results in the Human Torch being fatally wounded.
Despite the flames spilling out of the long-time hero, Invisible Woman is still able to approach her brother. She refuses to leave his side, even after he loses control of his powers. But using her powers, Invisible Woman is able to effectively sit with him as he burns up and is reduced to ash, simultaneously saving the lives of the fellow heroes in the room by containing them within a small shield. No one is hurt in the ensuing blast, including Sue, who almost casually used her powers to protect herself from the intense heat. However, she's left heartbroken by this turn of events, having lost yet another member of her family.
It's heartbreaking to see the Invisible Woman so shaken. In essence, she's now tragically the last member of the Fantastic Four left standing. Just the act of surviving meant holding her brother as he was reduced to ash. While this is a huge emotional blow to Susan, it's also a strong reminder of just how powerful she is. The Human Torch's abilities have been previously shown to be able to generate incredible heat, with his Supernova reaching the intensity of the sun.
And yet, despite this overwhelming amount of heat energy, Susan Richards was able to effectively create shields powerful enough to protect herself from flames intense enough to actually melt human beings without any obvious strain or effort. In effect, this version of the Invisible Woman effectively countered the Human Torch in his most powerful form, even if displaying the power came at the cost of severely shattering her emotionally.