Illyana Rasputina has been, for as long as she's been part of the Marvel universe, a fan-favorite character no matter what form she's taken on. As Magik, she's fought alongside her brother Colossus and the other X-Men, not to mention the Savage Avengers, taking down all sorts of terrestrial, alien and mystical threats. As Darkchylde, she has ruled over Limbo and spilled the blood of demons in her conquest of the realm. In the pages of X-Infernus, Illyana fought some of the toughest battles of her life as Darkchylde, cut off from her loved ones and allies, all to literally win back her own humanity.
Published originally in 2009, X-Infernus by C.B. Cebulski, Giuseppe Camuncoli, Jesse Delperdang, Dave Lanphear and Marte Gracia followed the aftermath of Illyana's untimely death. After the fallout of Inferno -- in which Illyana was the gateway for the demonic invasion of Earth -- the young hero emerged even younger, having de-aged from her Magik persona back into a young girl. Once returned to her family, she found herself at peace, if only for a moment, as it wasn't long after that she would become the first unfortunate victim of the Legacy Virus. The demon Belasco sought after Illyana's soul for his own nefarious purposes and resurrected her in her Darkchylde form. As Darkchylde, Illyana went to great lengths to try and restore her lost humanity, even taking a piece of Pixie's soul to craft a new soulsword with. Trapped in Limbo, the X-Men are coming to odds over how to handle the situation, with Colossus losing his patience with Cyclops' apparent refusal to do more.
Belasco's daughter, Witchfire, brings word of Darkchylde's quest to reclaim the lost pieces of her soul and restore her humanity to the Table of Demonic Overlords which her father used to have a seat at. She is in possession of the bloodstones and wants to take back her patriarch's former rule of Limbo for herself. Mephisto is willing to at least let her try, agreeing to give her a seat at their table should she be successful. Darkchylde is closer to her goals than Witchfire realizes though, as she ambushes the X-Men in the Danger Room after Pixie's soulsword took control of her while training with Nightcrawler. After stabbing her mentor in the chest, Pixie removed her dagger from his torso, dragging Illyana's soulsword out behind it, and Darkchylde has come to claim what is hers.
After taking her soulsword back from Pixie, Illyana is almost restored to her former self, though she doesn't spend any time explaining that to the other X-Men who arrive on the scene, including her brother. The X-Men now know without a doubt that she is still alive, and they form a team to go into Limbo and recover her. Nightcrawler leads Colossus, Rockslide, Pixie, Mercury and Wolverine into Limbo, and the group lands right in the thick of things when they arrive.
Illyana, in chains, tells Nightcrawler that he's their last hope, begging him to stab her with Pixie's dagger. Doing so draws forth Illyana's soulsword and allows Kurt to turn the tide of battle. In spite of this, Witchfire takes a second piece of Pixie's soul, completing the Bloodstone Amulet and calling forth the Elder Gods to wreak havoc on this plane of existence. The X-Men aren't done fighting though and dive headfirst into a scrape with literal gods while Magik goes to deal with Witchfire.
Witchfire isn't concerned, at least not until Illyana doesn't even flinch in the face of her powerful magic. Illyana has donned the mutant Mercury, who is invulnerable to magic, as a living suit of armor. Mercury makes her presence known and helps Illyana strip Witchfire of her amulet. With the combined might of herself and Pixie, Illyana is able to sever the amulet's full power, though they lose the amulet and Witchfire to the ensuing vortex. Pixie, unable to deal with the loss of more of her own soul, takes off on her own.
Illyana, believing herself a monster, is hesitant to rejoin the other X-Men back on Earth, but acquiesces to their pleas. From that point forward Magik would go on to become a regular fixture of the various X-books at the time. More than an action-packed adventure through Hell and back, X-Infernus shaped and defined a key part of the Marvel universe for years to come in just four short issues.