Sometime after their induction into the Avengers, the Young Avengers again decided to disband due largely to Wiccan's urging. Teddy and Tommy moved in with the Kaplans, but Tommy moved out a short time later.[7] Kate began working with Clint Barton,[29] while Teddy used his shapeshifting power to take on the identity of other superheroes to continue his heroics in secret.[7]

When Billy learned about the secret superhero acts of Teddy, they had a fight which ended with Billy searching the Multiverse for a reality where Teddy's mom wasn't dead and transport her to their reality. Wiccan was unaware he had been being manipulated by Loki, the responsible for the following events, in an attempt to control Billy, knowing he was destined to become the omnipotent Demiurge.[7] Instead of taking Teddy's mom, Wiccan accidentally took an interdimensional parasite called Mother.[7]

Billy and Teddy were saved from Mother's grasp by Loki,[30] and they were soon joined by other young heroes, Miss America,[31] Noh-Varr, and Kate.[32]At this point, Mother had taken control over numerous adults, and had used her powers to revive the deceased parents of these young heroes. When they were cornered in Central Park by their resurrected parents and an army of mind-controlled adults only they could see, Loki convinced Wiccan to lend him his power for ten minutes to save them all with his better skill at magic than Wiccan. As soon as Loki acquired Billy's powers, he disappeared, abandoning the group.[32]

 

While he intended to leave them to die, Loki had an internal conversation with his late child self, and was convinced to return to the team and empower them. After defeating Mother's army and escaping, the parasite faded away. Loki explained they couldn't go back to any place their parents were or had died (in the case of any deceased parent brought back by Mother) or Mother would return, as her powers were distance based. The young heroes decided to stay together and travel through the universe.[33]

In the next three months, Billy was trained by Loki to be prepared to fight Mother, with the ulterior motive of gaining his trust. The Young Avengers were joined by Prodigy, who informed them Speed was kidnapped by a strange entity dressed as Patriot.[8] The Young Avengers chased the entity through the Multiverse, who brought them to Mother's Dimension. They escaped, but accidentally left Prodigy and Hulking behind.[34] Using numerous evil alternate version of themselves as a distraction, the Young Avengers distracted Mother and save Hulking and Prodigy. Back to Earth-616, Hulking left the team to figure out if he really loved Wiccan or if his feelings were merely a consequence of Billy unwittingly using his reality-warping powers to influence their romance, an unshakable discomfort Loki planted in Teddy's mind.[35]

Teddy sought for help with Leah, who tricked him into returning to New York City, allowing Mother to come back to Earth-616, and threaten to unleash the evil versions of the Young Avengers to the world.[36] Since Billy was still too weak to end the spell which brought Mother, Loki suggested that he would be able to do it if his body were older, thus making Wiccan age him into a young adult. Unfortunately, Loki claimed that his powers didn't remain. The trickster revealed he had a second plan, to turn Wiccan temporarily into the Demiurge, his form with all of his potential unleashed. After Prodigy called all the teenager heroes available to fight Mother, the team headed out to confront her.[37]

During the battle, it was revealed Leah and her Young Avengers were actually a physical manifestation of Loki's guilt and the missing powers which he subconsciously gave up due to his guilt over killing his younger self.[38]Loki finally confessed his crimes, the murder of his younger self and the manipulations the Young Avengers had been victims of. His confession made Leah and her Young Avengers disappear, thus Loki regained his powers and freed Teddy. Hulkling comforted Billy, and reconciliated with him. Their reunion allowed Billy to become the Demiurge and destroy Mother. The team returned to Central Park where they were met by Billy's parents, but before he could introduce them, they realized Loki was gone, having fled the scene wracked with guilt over his actions.[39]

Celebrating Mother's defeat, the Young Avengers threw a New Years' party, along with many young heroes that had come to their rescue.[40] During the part, Prodigy was confronted by the entity who had kidnapped Speed, and after he discovered the entitiy's true nature, the entity returned Speed, who joined the Young Avengers in the party until it ended.

When the team departed the place using one of Miss America's portals, Loki, from behind, took a photo of the moment.[41]

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From http://marvel.wikia.com/wiki/Young_Avengers_(Earth-616)

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