WARNING: The following contains spoilers for S.W.O.R.D. #2 by Al Ewing, Valerio Schiti, Marte Gracia & VC's Ariana Maher, on sale now

Across its decades-long history, the X-Men has included dozens of heroes who've worked to protect a world that hates and fears them. But since every X-Men team only has a fraction of that many members, there are plenty of X-Men keeping out of the spotlight at any given moment. But sometimes, it only takes one action to bring a major hero back into the spotlight.

After not taking a major role in the current era of X-Men stories, Sunfire -- with a little help from a potentially dangerous figure -- just reminded everyone during the invasion of Knull just how powerful he really is in S.W.O.R.D. #2, and why he earned his rank as an Alpha-Level mutant.

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Sunfire was one of the first mutants who first encountered the original X-Men in their early days in Roy Thomas and Don Heck's X-Men #64 in 1970. Although he didn't leave their first encounter as friends, it certainly wasn't as enemies. He even proved willing to fight alongside the newly recruited second generation of X-Men in Giant-Size X-Men #1 by Len Wein and Dave Cockrum, helping the team overcome Krakoa and rescue the original team from its grasp. Although Sunfire soon departed after this victory, he's remained an occasional ally to the X-Men ever since -- working with them at various points and even briefly joining the team in the Decimation era. He's also one of the near countless mutants who've joined the new mutant nation of Krakoa, helping foster the future of the mutant race, although he hasn't taken any major role on the island.

Sunfire is among the many mutants who find themselves defending their home from the reach of Knull during his attack on the Earth. Sunfire throws himself into the battle and is knocked back in the process. Caught up by one of the symbiote dragons, Sunfire is sent crashing back to Earth. Although his natural flames keep the symbiote from infecting him, the impact of the blow is enough to leave his body broken and on the ground in Krakoa. However, Fabian Cortez is able to reach him and use his own mutant ability -- to unleash the full potential of other mutants -- to give Sunfire the strength and resolve to fly back into battle.

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This power boost is more than enough for Sunfire to unleash a torrent of flames, becoming something of a makeshift sun for Krakoa, which stands out now that the Earth has been so covered in darkness by the coming of Knull and his armies that even the natural sun has been blotted out. The attack is strong enough to knock the dragon out of the sky and keep Sunfire flying through the air, empowered and fully unleashed. It's a powerful reminder of the sheer power at Sunfire's fingertips, especially when he's fully unleashed. If the X-Men try to come up with more back-up plans going forward in case of emergencies such as King in Black, then having Sunfire on stand-by as a potential light and energy source could be an incredibly potent tool for the X-Men.

However, it's also a reminder of how powerful Fabian Cortez can be as well. Even with the former villain saying he's trying to overcome the addictive aspects of his power-boosting abilities, there's still the chance that Sunfire could end up under the thrall of Cortez. Sunfire could even prove to be a surprisingly dangerous ally for Cortez to recruit, considering the former Acylote is already angling to speak with the Quiet Council about their views on non-mutant "flatscans." While Sunfire is able to remind everyone of just how powerful he is during the battle against Knull, it's always worth remembering how dangerous it could be if pointed elsewhere.

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