Ellie Phimister
Alias(es) Negasonic Teenage Warhead
Appeared in Deadpool
Deadpool 2
Status Alive
Actor Brianna Hildebrand
"Negasonic Teenage.. What-The-Shit!? That's the coolest name ever!"
―Deadpool to Negasonic Teenage Warhead[src]

Ellie Phimister is a mutant who possesses powers to detonate atomic bursts from her body.



Negasonic is a trainee under Colossus at Xavier's school for gifted youngsters. When Deadpool had caused numerous traffic collisions on a highway while fighting Ajax and his men, Colossus and Negasonic flew in the Blackbird to his location. As Colossus tried to convince Deadpool to join the X-Men, Negasonic watched and was annoyed by Wades behavior who pointed her out as the stereotypical mean teenage girl which she agreed with. When Ajax managed to escape Deadpool attacked Colossus out of anger only to break most of his limbs. As the two prepared to take him back to the X-Mansion Deadpool cut off his own hand and escaped into a garbage truck. When Ajax kidnapped Wades girlfriend Vanessa he went to the X-Men to get the help of her and Colossus. Arriving at the location of where Ajax was holding Vanessa which was at an abandoned aircraft carrier Wade engaged Ajax while Negasonic Teenage Warhead and Colossus took on Angel Dust. To save her mentor who was being strangled by Angel Dust she used her explosive powers to knock Angel Dust out which also destroyed the aircraft carrier and knocked her out as well. Colossus however got both of them to safety and the two later helped locate and rescue Vanessa. After Wade killed Ajax he and Vanessa reunited while Colossus and her left with Negasonic finally acknowledging him as cool.

Deadpool 2/Once Upon a Deadpool

Negasonic Teenage Warhead was at the X-Mansion with fellow her X-Man and girlfriend Yukio when Colossus brought Deadpool there to recover physically and emotionally after the latter blew himself up over the death of his girlfriend Vanessa. When Colossus convinced Deadpool to join the X-Men, she joined them on a mission to stop a mutant causing trouble at the Essex House for Mutant Rehabilitation. During the mission, Deadpool managed to talk the young mutant, Russell Collins, down but then proceeded to kill some of the orphanage's staff when he learned that they were abusing Russell. Deadpool was subsequently arrested.

Colossus, Negasonic and Yukio later travelled to the Essex House to back up Deadpool, Cable, and Domino in taking on Juggernaut. Negasonic and Yukio helped to evacuate the children from the orphanage, then assisted Colossus in taking down Juggernaut.

Sometime after, Negasonic and Yukio repaired Cable's time travel device and gave it to Deadpool, allowing him to travel though time to save Vanessa Carlysle and Peter, and to kill an earlier incarnation of himself and Ryan Reynolds before he made Green Lantern.

Character traits

Negasonic Teenage Warhead is pretty much exactly what the opening credits of the movie said she is: A Moody Teen. She is sarcastic, unmotivated, very antisocial, and even her outrageous mutant name is a good indicator of how little she cares what anybody thinks of her. There really isn't anything particularly endearing and heroic about her besides the fact that she is on the side of the X-Men, among other "heroes". Although she remains obedient to her chivalrous teacher, she treats her duties as a hero mostly like chores she cares little about, and would even take a moment to write a Twitter post on her phone right at the start of a battle.

Besides her super human abilities, she is no different than a normal angsty teenager. She is snarky, rude, and isn't afraid to insult people whom she doesn't like, especially Deadpool. Though she does eventually warm up to him, calling him "cool." She does crack a smile at some points, especially when Deadpool makes a fool of himself.

Powers and Abilities

Explosion Creation & Manipulation: Negasonic is capable of generating explosions from her body of varying degrees. She can create a strong enough blast to push a van sideways with enough force to crush a human or a blast capable of toppling a grounded hellicarrier, as well as create a downward explosion capable of launching herself high into the air. She can even use her explosions in conjunction with a full body charge to attack superhumanly strong opponents like Angel Dust. Nega-Sonic does seem to require a certain amount of concentration and 'charging' time in order to better control the size/shape/direction of her explosions. Momentum also appears to play some part in the overall force and general direction of her explosions.



Behind the scenes

  • The original draft of the script had a lot of gun play and sword play, and director Tim Miller said he wanted to see more in the way of superpowers and traditional superpowers. As the writers looked for more characters, the name Negasonic Teenage Warhead jumped at them "because it was so cool, but we ultimately ended up changing her powers from the comics." In the comics, Ellie's powers are Telepathy and Precognition. Instead the writers went for exploding powers similar to Nitro - "We changed her to having this kind of explosive… because just the sound of the name - "Warhead" - implies to us that she could kind of become a human bomb, and we ran with that. There will be a few people offended by that, but she wasn’t a major enough character that I think we won’t piss too many people off."[1] It was the only thing the writers required Marvel's permission to do, asking Kevin Feige directly.[2] Feige, as it turns out, wanted something in return: James Gunn set up Ego The Living Planet to be Star-Lord's father without knowing that Fox owned the rights to Ego. As such, Marvel gave Fox permission to use Negasonic Teenage Warhead in exchange for Fox giving Marvel the rights to Ego. 


  • During San Diego Comic-Con 2015, Brianna described her character as a "15 year old superhero in training".
  • Ellie can be seen wearing an 'X-Men' uniform similar to the one from X-Men: First Class.
  • Brianna Hildebrand created a rock playlist for Ellie, which for obvious reasons included the song which inspired her codename (along with others by its band, Monster Magnet).[3]
  • Negasonic and Yukio romantic relationship is the first on screen depiticion of a LGBT relationship in a superhero film.



Promotion and Filming

Deadpool 2

  1. [1]
  2. [2]
  3. [3][4]
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