Spoilers for Marvel #4 ahead!

One of Doctor Strange’s greatest foes, Nightmare, has become so powerful that he is taking on, and defeating, some of the most powerful beings in the Marvel Universe, including the Celestials and Galactus. In the Overture sequence in Marvel #4, by Kurt Busiek, Alex Ross and Steve Darnall, readers get a horrifying glimpse of Nightmare on the cusp of godhood; the issue is available now in stores and on all digital comic platforms.

Nightmare is one of Strange’s most powerful enemies, and one of his oldest, first appearing in Strange Tales #110 way back in 1963. He rules over a “Dream Dimension” where he subjects captives to torture. Within the confines of this Dream Dimension, Nightmare’s power is absolute—he is a god. Doctor Strange first encountered him while helping an innocent man plagued by bad dreams, and the two have been adversaries ever since. Nightmare has gone on to become a threat to many more Marvel heroes, including Ghost Rider, Spider-Man and the Hulk. Now, Nightmare is taking the fight to the cosmic beings of the Marvel Universe—and winning.

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The issue opens with Nightmare standing triumphant over the bodies of Galactus and the Celestials; he has also impaled Ego the Living Planet in the eye. The heroes are also under Nightmare’s spell—Doctor Strange stands alone against Nightmare. After the issue’s other stories conclude, readers see Nightmare, now powerful beyond belief, ready to confront Eternity, the Living Tribunal and even Death herself. As Nightmare treads into battle, he tells Strange that the powers that made him a conqueror will now make him a god. It is then Strange realizes that Nightmare is using the power of dreams to reshape reality, and now he has to find a way to stop him.

Nightmare’s ability to control dreams has morphed into the ability to take those dreams and use them to alter the fabric of the universe. His alterations have attracted the attention of many of Marvel’s cosmically-powered beings. He has already dispatched the Celestials and Galactus—no slouches themselves; now the true heavy hitters stand in Nightmare’s way, and there is a genuine chance he will defeat them. How will Doctor Strange be able to stop Nightmare, especially since he has steam-rolled some the most powerful characters in the Marvel Universe?

Rumors are swirling that Nightmare will make his Marvel Cinematic Universe debut in Doctor Strange and the Multiverse of Madness, and this issue shows just how formidable a foe he can be-one capable of rewriting reality itself.

Next: Doctor Strange Almost Drove Galactus Mad