- "Mutants, I don't hate them. I just know what they can do. You don't realize this but we are at war. I took an oath: Protect this country. My name is William Stryker, and I am not a monster. I'm simply a patriot."
- ―William Stryker
William "Bill" Stryker Jr. is a covert operations specialist and military scientist. Known for his anti-mutant stance, he worked tirelessly over several decades to develop solutions to what he saw as the "mutant problem". Ironically enough, he himself was part of the problem as only males can pass the mutant gene to their offspring.
In 1973, Major William Stryker served as a personal assistant and bodyguard of Bolivar Trask. During the Vietnam War, William Stryker was an experienced helicopter pilot and flew many Black Ops missions into the jungles of North Vietnam, who sends him to an American airbase in Saigon, Vietnam where he attempts to subjugate several mutant soldiers, including Havok, Toad, Ink and Daniels to be brought in for experimentation at a Trask Industries laboratory. Mystique poses as an army colonel to interrogate Stryker's intention, and subdues him, taking the mutant privates back to America. Stryker tries to stop them escaping, to no avail.
X-Men: Days of Future Past Prologue
Following the Mutant GI's escape from Saigon, Stryker later accompanies Trask to the Paris Peace Conference held between the U.S. and Vietnam military leaders. Whilst there, Trask unveils to the generals present the prototype specs for the Sentinels and the mutant detection devices to be fitted into each of them, until he detects Mystique's presence in the room. Mystique reveals her true form and knocks out everyone in the room except Trask, who she shoots dead. However, Stryker recovers and quickly subdues her with a taser, then brings her in for experimentation.
Through the countless experiments that torture her, Mystique's DNA was mapped, reverse engineered, replicated, and installed into the most recent Sentinels, wherein the nature of her powers are distilled and used to enable the Sentinels' capability to imitate and adapt any mutant powers to counter their abilities. The killing, on the other hand, caused governments worldwide to fear mutants in general and initiate the Sentinel Program, with Trask as a martyr for the anti-mutant movement and Stryker spearheading the Sentinel initiative's development in his honor.
X-Men Origins: Wolverine Prologue
Some months after Trask's death, Stryker approaches James Logan and Victor Creed, after the mutant pair survived execution by firing squad. As he enters their cell, Stryker asks them to join his special team of mutants he is assembling, Team X, as a way out of imprisonment. Victor and Logan accept and join other mutants - Wade Wilson, Agent Zero, Chris Bradley, Fred Dukes, and John Wraith - on covert missions throughout the world.
During one of their missions, while under Stryker's command, Team X is sent to search for and retrieve a mysterious meteorite - later discovered as Adamantium - from a diamond trafficking operation in Lagos, Nigeria. They attack a compound there and after defeating the compound's security forces, they obtain a mysterious rock - later discovered as a meteorite fragment that fell from the sky as a meteor - from the compound's leader and discover that it originates from a remote village.
Upon arriving at the village, Stryker and the team them interrogated nearby villagers to see if there were any other meteorites and are informed that the rock fell from the sky as a meteor. Stryker wants more information and has Wade Wilson interrogate in his place because he speaks the language. When they threatened the village as to where the meteorite came from, the village chief refused to tell Stryker the origins of the meteorites, as they believe them to be sacred. After receiving no further answers, Stryker orders his team to attack the villagers by first ordering Victor to kill the chief. The whole village descended into chaos as Stryker's team started killing the civilians. When the mutants begin attacking a nearby village, Logan, however, stops them before they can do so.
After a brief argument with Victor, Logan quits the team, saying he can't kill innocent people as he was disgusted by the murders committed by his teammates, Stryker's willingness to kill innocent civilians, and Victor's acceptance of this. He promptly leaves and abandons Victor and the group before walking into the night and leaving, while ignoring Victor's calling out to him. With his departure, Team X disbands. Eventually, after everyone else left, only Agent Zero and Victor stayed faithful to Stryker.
X2: X-Men United Prologue
When William Stryker discovers that his son, Jason, is a mutant, he sends him to Xavier's School for Gifted Youngsters in the hopes of ridding his mutation, regarding it as a disease that needed to be cured. Xavier had no interest or belief in curing mutants, which angered Stryker. A furious Stryker was then encouraged to embrace Jason's mutation, and withdrew Jason from the program. Over the next year, Jason grew increasingly angry, resentful, and vindictive towards his parents and blamed them for his condition, to which he began to use his powers to torment them, planting horrific illusions and images in their minds.
Unable to handle the torturous illusions, Stryker's wife eventually committed suicide by applying a power drill to her left temple, and drilling into her own brain in an attempt to "bore the images out". Stryker then gave his son a lobotomy to make him more docile and kept him cryogenically frozen. Unable to cope with his wife's death, Stryker vowed to eliminate all of mutantkind.
During the next six years following Team X's disbandment, Stryker was promoted to Colonel and made Agent Zero and Victor his henchmen in order to abduct various mutants for his upcoming Weapon X project - Weapon XI. During this time, Victor captured Emma Silverfox, the sister of Kayla Silverfox, for experimentation. Stryker then gave Kayla the task of keeping an eye on Logan, who had left Team X and went back to Canada.
One day, Zero and Stryker visit Logan while at work to infrom him that Bradley and Wade were killed recently. Before doing so, Stryker asks Logan if he remembers Agent Zero, with Logan responds by asking Zero if he's still shooting first and asking questions later. Zero responds by pulling out his concealed gun, shooting Logan's Cigar, and, after putting away his gun, asks Logan a follow-up question as to if he's still chewing on cheap cigars. As Stryker tells Logan he has a job for him, Logan tells Stryker he already has a job. Zero humorously questions Logan's job payment as a lumberjack by asking if it pays 18 grand a year. Logan corrects him by saying his pay is actually 18.5 grand a year, before saying he hasn't had to kill anybody lately. Zero asks if Logan is starting to miss it, Logan, getting irritated, say now he is, before Stryker breaks them up, ordering Zero to the car, which he proceeds to do.
Victor agreed to go along with Styker's plan to trick Logan into agreeing to have adamantium bonded to his skeleton by claiming that Victor had gone rogue and Kayla Silverfox, Logan's' girlfriend, is supposedly killed in order to lure Logan for the adamantium process of the Weapon X program.
2 days later, after being brutally beaten by Victor, Logan wakes up in an emergency room, where Stryker happens to be present. Styker tells Logan he can help him exact revenge on Victor with an experimental procedure. Logan agrees to go through with it, but also warns that he is bent solely for revenge. Prior to the adamantium procedure, Logan asks for new dog tags with the name "Wolverine" on them - a reference to the story Kayla told him. Stryker binds Logan's bones with adamantium, making him virtually indestructible by grafting the metal compound onto his entire skeletal structure. Logan flatlined afterwards, but after a few moments, he resuscitates. After the process was successful, Stryker ordered Logan's memory to be wiped to protect the location of the Alkali Lake facility and so that his DNA could be used for an upcoming project. Logan escapes the facility after overhearing Sryker's plans. Stryker orders Zero to pursue him - eventually tracking him to a barn belonging to an elderly couple who had taken Wolverine in. After Zero failed in his mission, Wolverine took his receiver and announced his plans for killing the Colonel after killing Victor, as revenge to Stryker.
General Munson when confronted Stryker and tried to shut Weapon X down, and forced to halt To the Colonel's meant experimentations. The official claims that Stryker has gone too far as a result of his anger at the death of his wife. It is then revealed that this is due to his son, who turns out to be a mutant, indicating the source of his hatred of the mutant race. Learning of Stryker's son and believing that he was too emotionally close to the situation, Stryker kills General Munson. After Logan arrives on the Island, he finds Stryker, who tells him about Deadpool, and reveals that Kayla (present on the island) wasn't really killed; as Silverfox is revealed to be alive and was reluctantly working for Stryker.
As Victor is watching through the window from a nearby room, Wolverine was told that Victor and Stryker were subsequently working together to capture various mutants, culminating in tricking Wolverine into agreeing to have adamantium bonded to his skeleton by claiming that Victor had gone rogue and had killed the woman Wolverine loved. She had at some point been recruited by Stryker for the purpose of seducing Logan and creating an incident where he was compelled to join the Weapon X program and participating in the adamantium procedure - in this case, her faked death. With Victor Creed's assistance, her murder was faked with hydrochlorothiazide for Stryker, so he could trick Logan into participating in his Weapon X project. When Stryker claimed that Logan and Kayla's love was never real, she nods her head in denial, but Stryker silently threatens her with a concealed gun. After hearing how Kayla was working for Stryker, Logan left the facility to move on with his life.
Shortly after Logan's departure, Kayla confronted Stryker. She demanded he release her sister, who was also being held at the facility, only to be placated by him and told to wait. Then, Victor arrives and becomes angry at Stryker, both for letting Logan go and for reneging on their deal to bond adamantium to his body and demanded the adamantium procedure. The animosity between the Victor and James was made even worse when Stryker revealed that, contrary to his deal with Victor, he cannot merge adamantium to his skeleton because it would kill him as his healing factor is less powerful than Logan's, and isn't strong enough to allow him to survive the process. Kayla tried to persuade Victor that Stryker was only using them. After Logan returned to save Kayla from being killed by Victor, and defeated him, Logan and Kayla prepared to free the captured mutants. This enticed Stryker to order Weapon XI's activation, despite the bonding process being incomplete.
After freeing the imprisoned mutants, while leading them out of the facility, Logan, and the mutants are stopped and confronted by Weapon XI, Deadpool - now controlled by Stryker. Logan puts forth his best effort, but is pinned down. Just as Weapon XI is about to decapitate him, (at the command of Stryker), Victor shoves him away, and both of them fall into the reactor. Victor catches Logan, explaining the only reason he saved him was so he could kill him himself.
After Weapon XI failed to kill off Wolverine, and his mutant prisoners had escaped, Stryker readied a revolver, filled with adamantium bullets, which are the only things that can supposedly 'hurt' Logan. Carol Frost tried to convince Stryker that they won't work on Logan, due to the mutant's regenerative healing abilities. But Stryker claims that, although Logan's brain may physically heal, his memories "will never grow back". This claimed reveled that Stryker was attempting to take away Logan's memories, if the the latter can't be killed.
As Logan and Kayla were preparing to leave the island, Stryker walked up behind them and shot Logan with adamantium bullets in the back. In a feral rage, he turns and sprints at Stryker, eventually jumping after him. As he is in mid-leap, Logan is shot in the head twice by Stryker with adamantium bullets, and falls to the ground, unconscious - damaging his brain, causing amnesia, and forcing Logan to lose much of his long-term memory. Although the physical injury heal, his memories seem to be permanently gone.
This knocked Logan out long enough for Stryker to go after Silverfox but she turned the tables by touching his ankle. At first she forced him to put the gun to his own head but killing him was not her style or in her nature. Instead, she commanded him to drop the gun, walk until his feet bleed, and then to walk some more by saying "walk until your feet bleed...then keep walking." Stryker unwillingly proceeds to do so. Later, Stryker - exhausted and worn - is seen wandering down an isolated road. Then, military police in military vans arrived and approached the exhausted Colonel. An officer emerges and states that Stryker is wanted for questioning about his connection with General Munson's murder, which Stryker was charged of.
Between X-Men and X2: X-Men United
After Magneto's defeat at Liberty Island and capture by the authorities, William Stryker was notified and had him transferred into the hands of the Department of Domestic Security and Defense. His department had dealt with the incarceration of mutant subjects before, so they constructed a Plastic Prison to keep Magneto contained without an ounce of metal that could aid in his escape.
Stryker also used the rare opportunity of having Magneto in his custody, being well aware of his connection with Charles Xavier, to interrogate him via the use of a mesmeric serum from Jason to discover more about their past together. Through Magneto, he became aware of the existence of Xavier's Cerebro in the subbasement of the X-Mansion and what it was capable of. Seeing the possibility to wipe out mutants for good, Stryker set about formulating a new plan.
Stryker re-emerged from hiding to enact his new agenda, by using a fluid secreted from Jason's brain to control mutants, such as Nightcrawler and Lady Deathstrike. He brainwashed Kurt Wagner into assassinating President McKenna to justify an attack on the X-Mansion.
In the President's office, William Stryker is discussing the reaction and asks for authorization for a special operation. Just then, Senator Kelly enters (actually, Mystique in disguise, as the real senator is supposedly dead). President McKenna introduces the two men. Stryker then shows them photographs of Xavier's Mansion, saying that it hosts mutants. McKenna asks where he got the information from, and he answers that from an interrogation of one of the mutant terrorists from the Liberty Island incident. Mystique almost blows her cover, calling Magneto by his first name, but corrects herself and asks Stryker if he has access to Erik Lensherr. Stryker confirms, saying that they developed the technology that built his plastic prison.
Kelly looks at the photographs and says that the facility is only a school, but Stryker has a hard time believing that, showing them radar images of a jet hidden under their basketball court. That's all it takes to convince the President, he tells Stryker to enter, detain and question, but the last thing they need to see is the body of a mutant kid on the six o'clock news. Stryker leaves the office, and Kelly calls after him in the hall. Stryker introduces Kelly to his personal assistant, Yuriko Oyama, and Kelly comments on her strong handshake. He then asks Stryker if it's possible to arrange a visit at Erik Lensherr's prison. Stryker says it is not possible, as he's the enemy in this conflict. Kelly isn't happy with the word "conflict" and asks Stryker if he really wants to turn it into some kind of war. Stryker says that this already is a war and leaves with Yuriko.
In Magneto's prison cell, Stryker and his guard Mitchell Laurio come for a visit. Once inside, Laurio hits Magneto for Stryker to inject him with the mind-controlling drug. When the effects of the drug begin to work the guard leaves. Stryker tells Magneto that he wants to have one final talk about the house that Xavier built, as well as the machine called Cerebro.
Since Stryker expects Xavier to investigate the assassination attempt, he sends Yuriko to intercept him en route to meeting Magneto, also capturing Cyclops in the process. He eventually brainwashes Cyclops in the same manner. During the evening, Stryker's military forces led by Sergeant Lyman invade the X-Mansion. While there, his soldiers are able to capture several students (though most flee). In the front yard of the school, out of one of the helicopters, Stryker steps down.
Wolverine stays behind to confront the attackers but suddenly, Stryker's voice is heard, telling them not to shoot him yet. Stryker calls him by codename and says that it's the last place he expected to find him in – he hasn't seen him in over 15 years. Stryker, himself surprised to see Wolverine - the man he had worked with, experimented on, and severely injured decades earlier - in the mansion, reveals that he knows much about Wolverine. Logan doesn't remember Stryker and asks him who he is. Before he can answer, though, a thick shield of ice separates them, Rogue and Bobby call Logan to come. Wanting to get answers, he tells them to go, he'll be fine, but Rogue says that they won't. Stryker bombs the ice, but by then Logan and the kids are already heading to the garage and get into Cyclops's car.
In the underground tunnels, a soldier reports to Stryker that most mutants escaped through tunnels they weren't aware of, but they have six in custody. With special lasers, they manage to open Cerebro, and Stryker steps inside. He orders his soldiers to take what they need.
In Alkali Lake, Canada, Xavier is tied to a chair with a weird looking helmet on his head. He wakes up to find William Stryker sitting in front of him and Yuriko Oyama standing by the wall. The helmet keeps him from entering Stryker's mind. He asks him where Scott is. Stryker tells him not to worry – he's just giving him some re-education. Xavier realizes that this has to do with Stryker's son, and tells Stryker that he wanted him to cure his son, but mutation is not a disease. Stryker angrily accuses Charles of lying and tells him that back when Jason returned from Xavier's school he resented his parents, blaming them for his condition, so he toyed with their minds, projecting visions and scenarios into their brains. Mrs. Stryker, eventually, killed herself in an attempt to get the images out. Xavier sees Lady Deathstryke and tells Stryker that for someone who hates mutants, he hangs out with them a lot. Stryker shows him Yuriko has a controlling device on her back to keep her under control. Xavier suddenly realizes that Stryker arranged the attack on the President, and Stryker congratulates him on figuring it out without reading his mind. Yuriko leaves the room, and Stryker tells Xavier that it's frustrating that nobody really knows how many mutants exist or how to find them – except him. Unfortunately, he says, Xavier is too powerful to be mind controlled, so he'll go straight to the source. He then introduces Xavier to "mutant 143" – a young sick-looking mute man on a wheelchair, with pipes connected to his brain as a mind-controlling agent. Xavier, to his horror, immediately recognizes him as Jason Stryker, and asks William in shock how he could have done this to his son. Stryker answers "No, Charles, my son is dead, just like the rest of you", and leaves.
In the Control Room, a soldier tells Stryker that there's someone coming down the spillway. Stryker looks at the screens, and upon seeing Wolverine, tells the soldier not to flood it yet. Wolverine walks down the spillway and yells Stryker's name, his echo heard everywhere. He looks straight into the surveillance cameras and calls him again. Secret doors open in the spillway and soldiers with guns step through them and put handcuffs on Logan. The main door opens and they walk through it, into the base. Stryker, Yuriko and more soldiers meet them inside. Stryker orders to seal the room, but just then Wolverine jumps and kicks the soldiers around him, shifting to Mystique in the process, uses a soldier as a human shield from the guns and slides through the sealing door at the last second, all in mere seconds. Stryker enters the control room and tells the guy operating that they have a mutant lose and it could be anybody. When the soldier turns his back, Stryker hits him and seals the door. The soldiers and the real Stryker arrive too late, and the door is sealed and can only be opened from inside. Stryker orders a soldier to shoot a camera, and he does. Inside, Mystique reports to the others she's in and opens the spillway doors. Soldiers report to Stryker that more mutants are entering the base, but they can't see how many because of an electrical interference. Stryker orders to gather the soldiers and meet him outside Cerebro while two others are trying to open the Control Room doors.
Later on, all soldiers are set to defend Cerebro. Stryker enters the code and steps inside, seeing his son and Xavier. He leans and whispers to Jason's ears that it's time to find their friends – all of them – all the mutants, everywhere. In the illusion, the girl asks Xavier if it's time to find their friends – all of them – all the mutants, everywhere. Xavier agrees. Stryker tells his son to make him proud and leaves Cerebro. In the illusion, Xavier puts on the cerebral helmet and tells the girl not to move. Outside, Stryker orders the soldier to kill anyone who approaches, even if it's him. While walking to the hallways, Stryker and Lady Deathstryke look at the water pressure meters, and the Colonel panics.
Wolverine runs off on his own to look for Stryker and comes across an adamantium smelting room. Stryker and Lady Deathstryke enter, and Stryker starts explaining to him about how he has to keep the adamantium hot and liquid because once it cools it's indestructible. Stryker leaves and tells Wolverine that he used to think he was one of a kind – he was wrong. Logan runs after him, but Yuriko blocks his exit and tosses him across the room.
Outside, Stryker takes the cables keeping the helicopter on the ground off, but just then Wolverine shows up, punches him and pops his claws in his arm. Logan yells at him for experimenting on him and stealing his life, but Stryker tells him that he volunteered for the procedure willingly. Wanting answers, Logan asks Stryker who he is, but Stryker tells him that he's nothing but a failed experiment, provoking Logan into digging his claws deeper into Stryker's arm. Stryker doesn't want the mutant to remember the work they did together – he was an animal then, he's an animal now, Stryker just gave him claws. Suddenly, they hear an alarm going off then water burst out of the dam. Logan asks Stryker what's happening, and Stryker tells him that the spillway is about to get flooded because he was trying to relieve the pressure. In an attempt to escape alive, Stryker says that it's too late for anyone who's inside to make it out and offers him to come with him and get all the answers he wants – he's a survivor, always has been. Wolverine repeats Stryker's former words, saying he's just an animal with claws – if they die, he dies. He then pops his claws in Stryker's neck and ties him to the helicopter's leg with the cable before running back in.
Magneto, wearing a helmet designed to shield against telepathic attacks, is able to reach Xavier while the X-Men are incapacitated by the psychic assault. Per Magneto's directions, Mystique impersonates Stryker and instructs Jason of a change in plans - to kill all humans, which Jason then communicates to the brainwashed Xavier. Stryker manages to get himself out of the cables, but before he can get up, Cerebro's effect gets to him and he grabs his head in pain, Stryker is shocked that Cerebro II is turned against him as he writhes in pain, just like every other "white light" in Cerebro, including President McKenna.
After Dark Cerebro is reprogrammed, Stryker is shown to be in the same pain as every other human much to his shock. Later on, Magneto and Mystique come across Stryker once again, Walking to the suffering Colonel in amusement. Magneto ties Stryker to a concrete wall with the metal chain. Magneto, Mystique, and Pyro use the helicopter as an escape vehicle and leave Stryker to die. When the X-Men and the students make their way back to the Blackbird, Logan, carrying Artie Maddicks, comes face to face with Stryker one last time, who asked "Who has the answers, Wolverine? Those people? That creature in your arms?". Looking at Artie, Wolverine puts him down, dropped the dog tags Stryker fashioned for him years earlier and informs Stryker that he would "take his chances with him" and left him to die, by leaving him at the mercy of the collapsing dam. As Wolverine walks away, Stryker bellows after him that "One day! Someone will finish what I've started Wolverine! One day! One day!" Artie sticks out his blue tongue as reply.
Given his immobilised status, Stryker dies when the nearby dam bursts. Wolverine and Artie Maddicks were the last two people to see Stryker.
According to Charles Xavier, William Stryker was not simply drowned when the dam at Alkali Lake burst, but was disintegrated by the sheer force of the water pressure pummeling his body, a fate that would have beheld Jean Grey, if her powers did not shield her in a cocoon of telekinetic energy.
Following the Mutant GI's escape from Saigon, Stryker later accompanies Trask to the Paris Peace Conference held between the US and Vietnam military leaders. Whilst there, Trask unveils to the generals present the prototype specs for the Sentinels and the mutant detection devices to be fitted into each of them, until he detects Mystique's presence in the room. After Mystique subdues most of the guards in the room and prepares to kill Trask, Stryker tasers her and attempts to bring her in, until Professor X, Magneto, Wolverine and Beast intervene, and Magneto uses his powers to attach the tasers onto him instead.
Whilst he is incapacitated by his own taser, Logan looks down at Stryker and experiences a flashback to Stryker's involvement in Weapon X. After recovering and removing the taser from his body, Stryker spares a fleeting glance at Wolverine's bone claws, before running out of the conference room. Later, Stryker is present at Trask's side when he unveils the Sentinel designs to President Nixon in the Oval Office, as a response to the impending mutant threat posed by Magneto and Mystique.
He then accompanies Trask to the public demonstration of the Sentinels outside the White House, expressing surprise at the Sentinels' remote activation at the hands of Magneto. Once the Sentinels begin attacking the humans at Magneto's behest, Stryker shepherds Trask into the White House's Presidential bunker for their safety. Whilst in the bunker, Trask is alerted to the presence of a mutant inside the bunker, prompting the Secret Service agents and Stryker to pull out their weapons to subdue Mystique. Magneto uses his metal powers to cause their guns to hit the roof, prompting Stryker to pull out his plastic gun, which a disguised Mystique takes off him during the commotion. Magneto pulls the bunker out of the White House in an attempt to kill Nixon, and Mystique uses Stryker's plastic gun to shoot Magneto in the neck, incapacitating him.
Mystique later poses as Major Stryker to fish Wolverine out from the Potomac River, where he was flung by Magneto, and states that she will take him under her care.
After the destruction of the X-Mansion, a chopper descends to the ground. Moira MacTaggert approaches them, thinking they are part of another agency, until the leader steps out and removes his sunglasses. It's William Stryker. Raven notices him and tries to warn everyone, but Stryker orders his men to fire a sonic blast that incapacitates everyone, except for Scott Summers, Jean Grey, and Nightcrawler. Jean manages to keep them hidden by manipulating the mind of one of Stryker's men. Stryker captures Moira, Hank, Peter, and Raven. Nightcrawler teleports himself, Scott, and Jean into their chopper, but he cannot get anyone out because of the electrical lining within.
Stryker takes everyone to his facility and traps Moira and the mutants in a room. After the four wake up, Mystique calls out to Stryker, who greets Mystique, who in turn addresses him as "Major Stryker", but he corrects her, saying it's "Colonel Stryker" now. He tells the four not to get too close to the walls, for it may create some discomfort. Moira introduces herself and points out that she is a senior officer of the CIA, but Stryker says he knows who she is. Moira says that he can't keep her imprisoned, but Stryker says he can. He explains the psychic event that destroyed every nuke from the Alkali Lake all the way to Moscow.
That event emanated from where Stryker found the X-Men, at the home of the world's strongest psychic. Stryker then demands that the four prisoners tell him where Charles Xavier is. Moira tells Stryker that it's not Xavier he should be worried about, because there is someone else, someone more powerful out there. Mystique says that if he lets the four of them out, they can help. But Stryker refuses, asking Mystique if she really expects him to believe what she says. Stryker proceeds to tell Mystique that she can put on any disguise she wants, but he knows who and what she is. Stryker then walks off.
Charles Xavier, thanks to Apocalypse enhancing his telepathic powers, sends a message to everyone in the world, which is heard by all. After Charles broadcasted his message to the world, Stryker confronts his prisoners, noting that he recognizes that voice belonging to Charles Xavier, and once again asks them where the telepath is, wondering what's happening. But they all inform them that they don't know.
Jean Grey, Scott Summers, and Nightcrawler are noticed by Strker's men, and Stryker tells his men to send a security team to take out the intruders. Wolverine gets loose thanks to Jean Grey, causing the facility's alarm to go off, as Wolverine proceeds to kill Stryker's henchmen. Seeing Wolverine slaughter everyone's in sight, and knowing that berserker is heading his way, Stryker leaves, claiming that he'll be right back, but in truth, he makes his getaway in one of the helicopters.
Following Apocalypse's defeat and demise, Moira MacTaggert has Stryker arrested for his recent crimes and treachery: assaulting and kidnapping her, a federal officer, and for issuing unruly punishment to minors. Stryker warns her that mutants should not be trusted, and when that day comes, she better hope he's there when it happens. Moira watches as Stryker is taken away, and nonchalantly ignores his words on how untrustworthy mutants are.
A profound mutant-hater, William Stryker had served and protected his country for decades until he concluded that the main threat against the United States and its interests was not from opposing countries, but rather from within. Thinking the greatest threat to the world was mutants, Stryker became extremely paranoid and was dedicated to advancing the military to combat with these mutant problems should the need ever arise to, going by means of illegal experimentation on mutations. Though he has prioritized global and national security, Stryker has single-handedly caused social upheaval by implicating mutants in the assassination of the President of the United States in an attempt to turn them into public enemies so his attempted genocide on their species would be considered more acceptable. Stryker was also willing to kill his superiors if they went against his plans by murdering General Munson when he threatened to close the Weapon X Program.
Part of this intense hatred for mutants comes from Stryker birthing one himself. His son, Jason blamed him for his mutation, as it was usually passed along through the Y (male) chromosome. Furthermore, when he sent Jason to Charles Xavier's School for Mutants, Stryker believed his son was to be cured, only to discover that mutation was not a disease and this enraged Jason further, to the point where he tormented his mother and father to no end until Stryker's wife eventually committed suicide. Now with a personal incentive, Stryker's hatred only expanded until he set his goals on killing every mutant on Earth. Despite his hatred, though, Stryker found the usefulness of using mutants, at least those who he could control such as Lady Deathstrike, Nightcrawler and Cyclops. His basis on this was thinking that the only effective way to kill mutants was with mutants by building the ultimate mutant killer - Weapon XI. However, the original Team X was not mind-controlled with Sabretooth and Agent Zero being of their own free mind and will but it was presumably Wolverine, Wraith, Dukes, Wade and Bradley leaving that prompted Stryker to using mind control. Having studied mutants for years, he knew how to counteract with different threats opposed by individual mutants unique and varying powers such as building a plastic prison to contain Magneto, a device that prevents Professor X from taking control of anyone's mind and giving Lady Deathstrike an adamamtium skeleton and regenerative healing factor that was able to match and evenly duel with Wolverine, including adamantium nails similar to Logan's claws.
- Genius-Level Intellect -
- Expert Scientist
- Skilled Leader -
- Agent Zero † - Former Teammate and Former Bodyguard
- Bolivar Trask † - Former Superior
- Deadpool - Former Teammate and Experiment
- Weapon X
- General Munson † - Former Superior/Sponser and Ally turned Victim
- Kayla Silverfox † - Former Subordinate, Enemy, and Attempted Victim
- Lady Deathstrike † - Experiment and Former Bodyguard
- Artie Maddicks - Kidnap Victim
- Cypher - Kidnap Victim
- Emma Silverfox - Kidnap Victim
- Gambit - Kidnap Victim
- Jubilee - Kidnap Victim
- Jones - Attempted Kidnap Victim
- Siryn - Attempted Kidnap Victim
- Psylocke † - Kidnap Victim
- Daniels - Enemy
- Havok - Enemy
- Ink - Enemy
- Brotherhood of Mutants - Enemies
- Team X - Former Teammates
- X-Men - Enemies
- Daniels - Enemy
- Havok † - Enemy
- Ink - Enemy
- Jubilee - Enemy
- Magneto - Enemy
- Toad - Enemy
- X-Men - Enemies
- Stryker being a key figure from Logan's past is similar to that of the character Romulus in the comic series. 
- Stryker's lapel emblem in X-Men Origins: Wolverine is a homage to the comic character's evangelical preacher roots. 
- Stryker is one of only two people who can see through Mystique's disguises, the other being Wolverine. Stryker sees through Mystique's abilities whilst she is imitating Wolverine to enter Stryker's base at Alkali Lake. He states that "if there's one thing I know better than anyone, it's my own work". Although they both got tricked once in X2: X-Men United, while impersonating Jean Grey and Wolverine, till they realized she's an imposter.
- William Stryker is the second-most recurring villain in the X-Men film series, second only to Magneto. Both men believe that the motivations behind their actions are for the greater good.
- Despite his apparent hatred for mutants, he frequently operates with military teams composed entirely of mutants. Examples are his formation of Team X, his creation of Deadpool, his control over Lady Deathstrike and the fact that he decided not to kill his son for being a mentally-ill mutant and for killing his wife.
- A notable discrepancy exists between the two portrayals of Stryker by Josh Helman and Danny Huston respectively; although Helman's incarnation is meant to predate Huston's, Helman only wears military decorations from the Vietnam War (1955-1975), whereas Huston wears decorations from the Korean War (1950-1953) and the Vietnam War.
- According to his military dogtags in X-Men: Days of Future Past, William Stryker is a Protestant.
- In X-Men: Days of Future Past, Stryker has won the following military decorations (according to those apparent on his uniform):
- Silver Star (Ribbon) with "V" Valor Device
- Purple Heart (Ribbon)
- Meritorious Service (Ribbon) with "V" Valor Device
- National Defense Service (Ribbon)
- Vietnam Service (Ribbon) with Bronze Oak Leaf Cluster, indicating won twice
- Vietnam Campaign (Ribbon)
- Combat Infantry Badge
- Master Parachutist Badge (Army)
- Army Presidential Unit Citation
- His father, William Stryker Sr., has a minor role in X-Men: First Class. Stryker himself is mentioned by Xavier in passing, as his father was thinking about him during Xavier's meeting with the CIA.
- Bolivar Trask and William Stryker are dead in the original timeline but are alive in the revised timeline. Ironically, both of them are arrested for crimes relating to mutant persecution.
- A deleted scene from X-Men: Days of Future Past presents an alternate take on Logan's recovery from the Hudson River at the end, wherein Stryker is asked what to call him, simply responding "Just call him... 'X' ", a reference to Logan's status as "Weapon X", the culmination of Stryker's mutant experiments to synthesize adamantium bonding to a mutant's exoskeleton to create the ultimate mutant soldier. Additionally, the Stryker that was featured during this alternate scene appeared to be the real William Stryker, and not Mystique posing as Stryker as was shown during the final scene of the theatrical cut.
- In X-Men: The Official Game, a mistake is made regarding Stryker's rank. Although he was referred to as a general in the game, the highest military rank he attained was that of colonel before his death in X2: X-Men United.