Maybe being a bad father is a Summers’ curse. Introduced in X-Force #5 (1991) by Fabian Nicieza and Rob Liefeld, Tyler Dayspring is the son of Cable and his wife Aliya Dayspring, having being born in the Apocalypse ruled future of Earth-Askani. Inheriting the same powers as his father, he would grow up to join his parents as a freedom fighter. However, in a battle that saw the death of Aliya, Tyler was taken by Stryfe and brainwashed into being his shoulder. When the Clan Chosen raided the base, Tyler kidnapped the member Dawnsilk, forging a neural link with her to gain the Clan’s secrets. Cable had no choice but to sever the link by shouting Tyler. This cause a feedback between Tyler and Dawnsilk, further fueling his hatred for his father.

Using a time travel device, he traveled to the Prime present and became an arm’s dealer under the name Tolliver. He would learn about Cable arriving in the present and began planning his revenge. Working in the shadow, he pitted his father off against Stryfe, who had also come to kill Cable. He would also send agents to kill the Six Pack. At some point, he would kidnapped Domino and replace her with Copycat. He would also hire the likes of Deadpool and Gideon as his agents, sending them to attack the New Mutants, which would later be reformed into X-force. When Copycat refused to answer his summons, he sent Deadpool to remind her of her mission. This would eventually lead to his plans being reveal and the real Domino found. He decided to “kill” off Tolliver but making it seem he had died in a helicopter accident trying to escape.

When Cable was thrown through time, Zero, Stryfe’s android companion, would come into Tyler’s possession. They would eventually Cable’s body that now had Stryfe’s mind in it as well. He would later find another Clan Chosen member, Askani. Working with Mr. Sinister (who Stryfe tricked into releasing the Legacy Virus), he began playing mind games with his father and Stryfe, revealing their true origins, that Nathan was the real version and Stryfe was the clone. Cable would finally learn the truth behind Tyler and a battle between father and son, with Cyclops, Jean and Prof X helping to battle. When he learnt of Apocalypse’s supposed death, he decided to take his place, taking the name Genesis. He began using the Dark Riders as his minions, having them kidnapped Wolverine to try and restore the X-man’s adamantium. After pitting Cyber against Wolverine, Logan would escape before the procedure took place and killing the Dark Riders and Genesis. He was last seen as a vision along with his mother, living in peace in the afterlife, when Cable was infected with the Techno Virus during the Onslaught saga.