William Stryker Jr. was an army colonel set on destroying mutants. He once served as the right-hand man of Dr Bolivar Trask in the early 1970s, and is responsible for grafting the adamantium compund into Wolverine's skeleton, and the creation of Weapon XI (Wade Wilson). Over the course of his life he searched for various ways to destroy all mutants. His son Jason Stryker is also a mutant. During an encounter with the X-men, he was killed by a flood while trapped helplessly by Eric Lehnsherr.
X-Men Origins: Wolverine
In the year 1973, William Stryker came up to Logan and Victor to recruit them into his team of mutants - Team X. He then led the team over the next couple of years on various covert missions to find the metallic compound known as adamantium. Stryker finally found the adamantium he sought while on a mission in Nigeria. Stryker threatens to kill civilians to garner information, causing Logan to leave the team. Team X later disbanded, and only Agent Zero and Victor stayed on with Stryker.
Over the next six years following Team X's disbandment, Stryker made Agent Zero and Victor his henchmen in order to abduct mutants for his upcoming Weapon X project - Weapon XI. He tells Creed to kill all the other members of the team and to have Logan's girlfriend Kayla (Silver Fox) - an agent of Stryker's keeping an eye on Logan- fake her death. Stryker recruited Logan into becoming Weapon X (the tenth project of the Weapon X program), making him virtually indestuctible by grafting adamantium onto his entire skeletal structure. After the process was successful, he ordered Logan's memory to be wiped to protect the location of the Alkali Lake facility. This prompted Logan to escape, and Stryker ordered Zero on a failed mission to kill Logan.
While on his Three Mile Island facility, Stryker killed General Munson, his major military and financial sponsor, because the latter had threatened to end the Weapon X program due to Stryker's extreme personal vendetta against mutants, caused by his experiences with his son Jason who had caused the death of his wife.
After Weapon XI was decapitated by Wolverine, and after his mutant prisoners had escaped, Stryker shot Wolverine twice in the head with adamantium bullets, causing the latter lose his memory. Before he could shoot Kayla, she used her tactile hypnosis to make him drop the gun and walk until his feet bled. While still in a tracne, Stryker was later approached by military police, who wanted to question him about General Munson's death.
X-Men 2
Rather than having killed his son, Jason Stryker, at birth, William Stryker sent him to Professor Xavier's school in hopes of curing him, regarding mutation as a disease that must be cured. Xavier had no interest or belief in 'curing' mutants, which angered Stryker. Additionally, Jason continued to grow angry, resentful, and vindictive towards his parents; he tortured them by planting illusions in their brains until his mother committed suicide by drilling into her own brain in order to "bore the images out". Stryker then gave his son a lobotomy to make him more docile, making him Mutant 143, and allow him to derive a brainwashing potion from Jason to control mutants.
Firstly, Stryker brainwashes Kurt Wagner aka Nightcrawler into assassinating the President. Using the recent assassination attempt as leverage, he convinces the President to authorize an infiltration of the Xavier Institute, lying about his intentions. Just before the infiltration, he learns more about Cerebro from Magneto - who was being held as a federal criminal in a plastic prison (designed by Stryker). Magneto did not give the information willingly; he had to be brainwashed like Wagner. He kidnaps Cyclops and Professor Xavier (who were visiting Magneto in his plastic cell) and brainwashes them both. He attacks the X-Mansion after having learnt the information from brainwashing Magneto.
Jason, under his father's direction brainwashes Xavier- after Xavier learns that Stryker is the mastermind behind the assassination attempt on the President - into using a near-identical reproduction of Cerebro (identified as Cerebro II/Dark Cerebro) to kill all mutants, while Cyclops is left to confront the attacking X-Men. 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, but then he uses Cerebro II to kill all ordinary humans by making some adjustments to Cerebro II, and has Mystique impersonate Stryker and instruct Jason of the "change in plans", which Jason then communicates to the brainwashed Xavier after Magneto and Mystique escape.
Stryker attempts to flee the area by running to his helicopter, but his attempt is foiled by Wolverine, and Stryker tempts Wolverine to come with him so that the he could learn more about his forgotten past. However, Wolverine refuses the offer and decides to return to the dam to save his teammates, but before he does, he chains Stryker to the leg of a helicopter. Stryker frees himself and tries to escape again, but is then psychically assaulted by Cerebro II, which had been reprogrammed to kill all humans. During the psychic assault, Stryker is chained to a large block of debris by Magneto after he tells Stryker they won't meet again. Magneto and Mystique then leave the place using Stryker's helicopter. Meanwhile, Storm and Nightcrawler enter Cerebro II and disrupt Jason's illusion, allowing Xavier to break free from his control before any humans are killed. Nightcrawler teleports Storm and Professor X to safety before the dam collapses onto Jason.
In his last moments, Stryker is approached by Wolverine, and he asks Wolverine about how he apparently volunteered to have the adamantium put in his skeleton, and asks him whether he would actually side with mutants. Looking at the young mutant he was carrying to safety, a young boy with a lizard-like tongue (Artie Maddicks), Wolverine informs Stryker that he would "take his chances with him" and left him to die. As Wolverine walks away, Stryker bellows after him that "One day someone will finish what I've started. One day!" As the Alkali Lake dam ruptures, Stryker is killed by the immense water pressure released by the dam. Later, Xavier and the X-Men gave the President the files from Stryker's office containing the evidence of Stryker's crimes.
