The Universe X Rom
Universe X was a limited series set in an alternate Marvel Universe timeline and was the sequel to the well-received Earth X limited series. It takes place in the future, but certain aspects of the past are changed as well. I won't even attempt to summarize the plot, as it's very complicated and you don't need to know much.
In issue #3, Captain America, a reincarnated Captain Mar-Vell, and Kazar travel to Limbo. There they encounter Rom, back in his human form, who appears to be trapped there. Rom is using the front half of the torso of his armor as a shield and weilding his Neutralizer. He helps Cap & co. against the Dire Wraiths attacking them. Then Mephisto shows up. Discussion ensues and as Cap & co. are going to depart, Rom gives Captain America his Neutralizer to use against his enemies during his quest.
Incidentally, because Marvel no longer has the Rom license, he's never named. When Captain America first sees him, he exclaims, "the greatest of the Spaceknights!" (Yeah, that sounds natural.) After that, even the narrarator doesn't mention his presence.
In #4, Captain America attempts to use the Neutralizer to neutralize Death. Not only does it not work, it destroys the Neutralizer. And that's the end of that.
Rom's part is very minor. As a result, there are many unanswered questions.
- How was Rom's humanity restored?
- Why is he trapped in Limbo? With his Neutralizer, no less. The previous two times he was banished there, it was his own Neutralizer that did it, and it stayed back on Earth.
- Why was he so inspired to give Cap his only defense against the Wraiths?
- Why doesn't he leave with Cap???
There are a few errors, although since it's an alternate reality, you might argue that in the Universe X reality they're not errors.
- Both male and female Wraiths are red. The male Wraiths should be white. Laura DePuy, colorist of this issue, contacted me looking for color references on the portals Rom's Neutralizer opens. She mentioned her confusion about the Wraiths formerly being white but later being red. I explained it to her, but it was too late to change the issue. (And, as she said, "heck, it's a what-if story at heart anyway...")
- There are Hellhounds in Limbo. Rom's Neutralizer cannot banish Hellhounds, only restore them to normal dogs. (Although you wouldn't know it from the climatic scene in Rom #66.)
- Rom's Neutralizer is supposed to have safeguards built-in to keep anyone but Rom, in his armor, from using it. Therefore, not only should Captain America not be able to use it, but neither should Rom in human form.
- Mephisto claims Death cannot enter Limbo. (For arguments sake, let's say he's telling the truth for a moment.) If so, how does Rom's Neutralizer work in Limbo? He obviously can't banish Wraiths to Limbo when they're already there, so he'd have to kill them. Furthermore, the Avengers had no problems killing Wraiths in Limbo in Avengers #268. Perhaps we just have to assume Mephisto was lying after all.