With Marvel's new Ultimate Universe finding its footing in a world gone awry, it was only a matter of time before a new team arose to avenge the world that should have been. Ultimate Universe #1 (by Jonathan Hickman, Stefano Caselli, David Curiel, and Joe Caramagna) saw the unusual team of Doctor Doom and Iron Lad working together to free Earth-6160's Thor from imprisonment. In the process, they gained an unexpected member in Lady Sif.
Source：https://www.cbr.com/ultimate-avengers-sif-recruit-marvel/
