|For alternate versions of Alex Wilder, see Alex Wilder's Character Hub|
Alex Wilder was a former member of the Runaways who sought revenge against his former teammates after surviving a bomb attack he suspected one of them to have engineered. He traveled into the past, hoping to kill his former teammates before they were reassembled by Nico Minoru. However, he was prevented from doing so by Chase Stein, and subsequently captured by the Runaways. He was later erased from existence after Stein and the Runaways saved Gert Yorkes from death, thus significantly altering their original timeline.
In 2028, Wilder survived the explosion of a bomb that had been planted in his office. He investigated the origin of the bomb and became convinced that one of his former friends, the Runaways, had attempted to kill him. He therefore decided to exact revenge on them, but instead of attacking them directly, he chose to travel to the past and kill their past counterparts.
Traveling to the Past
Arriving in year 2021, Wilder decided to firstly target Nico Minoru before she could reassemble the Runaways in memory of Gert Yorkes, who had died three years before in the Battle at the Hostel against Morgan le Fay. He thus went to the house where Minoru was living and shot at her with his Energy Pistol, but Minoru blocked the bullet. This surprised Wilder, as he did not expect her to be able to defend herself with the Staff of One. Before he could move further, Wilder was subdued by Chase Stein, and decided to retreat.
Since the Runaways had managed to gather, Wilder decided to go after their loved ones and approached Julie, Karolina Dean's girlfriend. He knocked her unconscious using his Energy Gun, waiting to ambush Dean as she arrived to check on Julie. However, Wilder was once again stopped, this time by Minoru's spell. Interrogated by Stein about his time machine, Wilder refused to answer and took advantage of a moment of destruction to teleport away, to year 2017.
Wilder arrived in Atlas Academy, on the day prior to the discovery by the future Runaways about the Rite of Blood, planning to attack them as they were at their weakest. However, he was found by the 2021 versions of himself and Minoru, who chased him, followed by Stein. Upon fleeing, Wilder was caught by mistake in a bus full of students led by Kwan. As the other Runaways arrived, Wilder held another student hostage with his Energy Knife, before being incapacitated by another of Minoru's spells.
Wilder was brought to the school gym, where his past counterpart blamed him for his actions, but Wilder dismissed the blame, citing how he was only being pragmatic and had the courage to do what was necessary before claiming that Minoru had left her friends for selfish reasons. Later, when Stein explained that he wanted to time travel again to save Yorkes from her death and the other Runaways insisted to accompany him, Wilder warned them that such a drastic change in the timeline would erase their current selves. Nevertheless, the group maintained their decision, and took Wilder with them to the 2018 Hostel.
Upon arriving in the Hostel, Wilder was able to slip through the Runaways' hands. He hid in the mansion and wrote a note meant for his past counterpart, instructing him to hide Victor Mancha and kill Nico Minoru. Wilder then remained unseen, but reappeared when Chase Stein confronted Morgan le Fay, signaling how he was being protected by the future Nico Minoru before being knocked unconscious by Molly Hernandez.
In the aftermath of the Runaways' success, with the future Stein being killed by le Fay instead of Gert Yorkes, Wilder faded away from reality due to the change in the timeline that it brought, with his body being noticed by his past self.
In the aftermath of Gert Yorkes' death and the attempt on his life, Wilder's pragmatism and tendency to ruthlessness went extreme. Claiming that one of his former teammates had attempted to kill him, he decided to chase their past counterparts to kill them all in retaliation, showing no second-guessing of this extremely brutal choice as he considered them to be the result of pure self-preservation instinct. He was also willing to hurt the Runaways' loved ones, such as Karolina Dean's girlfriend Julie. When captured by the Runaways and confronted by his past and more pacific counterpart, Wilder did not express any remorse regarding his decisions, stating that he was only embracing his true nature.
- Energy Pistol: Wilder attempted to kill Nico Minoru with this weapon, only for her to block the energy bullet. He later used the weapon on Julie, rendering her unconscious.
- Energy Knife: Wilder wielded this knife during his infiltration into Atlas Academy, and threatened to kill a student with it before being stopped by Minoru.
- Chase Stein's Time Machine: Having helped Chase Stein to develop the time machine, Wilder possessed his own copy of the device, and used it to repeatedly leap through time in an attempt to murder his former teammates.