The Summers family is perhaps the most prominent tribe of mutants next to Charles Xavier's X-Men. Their bloodline has produced some of the most powerful mutants in the Marvel universe and, as such, having a surname of "Summers" in the Marvel comics is a quick ticket to the Omega level classification of mutant power (usually). For that to happen, though, dark and convoluted family dramas and tragedy have to happen.
For the Summers, it often came in the form of deception, betrayal, and more trips to the past and future than the amount of hair on your head (doesn't count if you're bald). Of course, you can bet that their family tree, starting with the Summers brothers, is confusing. There are powerful mutants left and right, and how they're connected is not always clear. However, 10 of them stand out for being more powerful than some of the godly beings of the Marvel universe. Here they are:
10 SCOTT SUMMERS (CYCLOPS)
Scott (or Cyclops) probably doesn't even deserve to be so high up on this list (trust us, this is high enough already). His mutant powers are quite simple: he shoots lasers. Well, actually the more intricate explanation is that his mutation allows him to absorb ambient energy (solar radiation, cosmic rays, or photons) and channel them as a beam through opening his eyes... uncontrollably, hence his special visor.
He doesn't really hold a candle compared to the likes of Professor X or Magneto. Still, it would be a crime not to include him in this list since he's directly responsible for the most powerful mutants further down this roster. It was his liaisons with certain powerful mutants that have created what can be considered by some as "perfect mutants," and the Phoenix Force (a powerful cosmic entity) goes crazy for those.
9 ALEXANDER SUMMERS (HAVOK)
We regret to inform you that Scott may actually be the weakest among the three Summers brothers. His brother, Alex (Havok) is pretty much like him and has similar powers. Instead of being able to project the energy with his eyes, however, Alex can let that bottled-up energy all out with his whole body. This makes him potentially more dangerous than Scott.
He even needed a special suit sometimes to contain his mutant powers and focus them. It's similar to Cyclops' visor. The difference is that Havok's is a lot more intense. Even he is immune to Scott's optic energy blasts. Furthermore, Alexander can also use his absorbed energy to give himself some controlled flight capabilities.
8 GABRIEL SUMMERS (VULCAN)
Gabriel (Vulcan) had the misfortune of being yanked away from Earth by the aliens. Technically, it was his pregnant mother who was abducted by a member of the royal family of the Shi'Ar empire (one of the biggest alien empires in the Marvel universe). Gabriel was extracted from the womb and placed in an incubation chamber, where he was immediately and rapidly aged into an adult.
Yes, apart from being an abductee, he also had no childhood. Nevertheless, Gabriel grew up to be the most powerful out of the Summers brothers. Like them, he can also absorb any energy and channel it in a violent manner. He can even use such energy to fly and heal himself rapidly. Too bad that didn't prevent him from dying after being swallowed by a sentient island on Earth.
7 NATHAN SUMMERS (CABLE)
Nataniel Christopher Charles Summers or Nathan (Cable) is technically Scott's first official child. Oddly enough, he's sort of illegitimate. He was borne to Scott and a Jean Grey clone made by Mr. Sinister. Scott eventually found out and left the fake Jean Grey clone. Regardless, this didn't prevent Sinister's plans to make Cable a genetically superior mutant.
Cable's powers, as a result of the union between Scott and a Jean Grey template, include telepathy, telekinesis, time travel, and the standard superhuman capabilities (speed, strength, endurance, and healing). Cable's also a master combatant and a crucial mutant in the future versions of Earth. That didn't prevent him from being constantly punked and ridiculed by Deadpool, though.
6 MADELYNE PRYOR
Remember that fake/clone Jean Grey (Cable's mother)? This is her real name. It was revealed once she found out that she was a mere copy made by another diabolical mutant. Madelyne was left by Scott once he found out that she was just a clone and that the real Jean Grey had been resurrected. As a result, Madelyne went ballistic and her cloned Jean Grey powers became amplified.
Initially, as a Jean Grey clone, Madelyne only had telepathic and telekinetic powers. After being manipulated into becoming the Red/Goblin Queen and as a result of being heartbroken by Scott, her powers grew even more. She developed the ability to warp reality, enhance her own strength, teleportation, and siphoning the psionic energy of other mutants. Of course, being modeled after Jean Grey, her volatile powers are already a given.
5 RACHEL SUMMERS (PRESTIGE)
Every member of the Summers family before this point has been on Earth 616 (a.k.a. the official Earth of the Marvel universe). However, some alternate reality Summers are simply too powerful to stay hidden in their own pocket of reality. Hence, we present you with Rachel Summers (Prestige). She's the legitimate daughter of Scott and the real Jean Grey in a reality where the Sentinels have taken over America (Days of Future Past comic books).
As a result, Rachel is pretty much a Jean Grey Jr. (she even inherited her hair). She inherited her mother's godly telepathic and telekinetic abilities. If you're not aware already, the Phoenix Force (one of the most powerful cosmic entities in the Marvel universe) regularly prefers Jean Grey as a host. Rachel, being similar to her mother, is also a Phoenix Force host. That means she can regularly tap into its power.
4 FRANKLIN RICHARDS
As some of you might have guessed already, Franklin is the mutant son of Fantastic Four's Reed Richards and Sue Storm. Hence, apart from his mutant capabilities of molecular manipulation, telepathy, and literally being able to create a pocket universe, he's also super smart. He's even said to be on the same level as the Celestials.
On the official Earth, he never really became a member of the Summers family. On the same alternate reality where Rachel Summers was born, however, Franklin actually married her and the two even had kids together. Basically, they were the X-Men's ideal power couple, both of whom could change the whole universe on their whim. It's too bad they only exist on an alternate Earth.
3 HOPE SUMMERS
While Earth 616 never really got something as stable and hopeful as the Franklin-Rachel mutant tandem, it still had Hope Summers. Hope is the adoptive daughter of Cable, making her Scott's adoptive grandchild. Nevertheless, she's proven to be a fitting member of the Summers family tree; she's somewhat of a messiah child. Hope was actually born after Scarlet Witch decimated the mutant population of Earth. Her mother was a human and her father was unknown.
As for why everyone's after the mutant messiah, Hope? She can basically mimic and control other mutant superpowers, enhance emerging mutant powers in other individuals, has telekinesis and telepathy, and she's virtually undetectable through psychic means. Hope was responsible for saving the basically endangered mutant race on Earth 616.
2 JONATHAN RICHARDS (HYPERSTORM)
That kid Franklin and Rachel had? He's named Jonathan (Hyperstorm) and he's simply too much to handle for Earth 616. Thankfully, he doesn't exist there; he's confined in the alternate reality of Franklin and Rachel. The dude is basically a mutant version of DC's omnipotent Superman (but evil). Jonathan was so powerful, he took over his own post-apocalyptic world as Hyperstorm and set it straight. Hyperstorm's powers include being able to manipulate reality, invisibility, telepathy, telekinesis, and extreme healing.
He didn't stop at his world: he also conquered other planets, galaxies, and nearly conquered most of the universe. He set out to conquer other timelines as well since he was dissatisfied with just his own reality. Hyperstorm was only "defeated" through Galactus, who consumed and took him into a dimensional void in the universe.
1 JEAN GREY
Well, what do you know? The most powerful member of the Summers family wasn't even a Summers. Not initially, at least. Jean Grey's power as an Omega level mutant is undeniable. Her regular self with the most powerful telekinesis and telepathy among mutants is already formidable. How she became the most powerful mutant ever is through the Phoenix Force.
Jean was the original and true host of the Phoenix Force. Once she bonded with the cosmic entity, she was able to travel through space and time. The Phoenix Force also essentially made her immortal, as she was able to resurrect herself with it. Jean has even defeated the likes of Galactus singlehandedly with the Phoenix Force. Scott, or even the whole Summers family tree, really lucked out on her.