Earlier Japanese-exclusive media such as "" and TV Magazine's manga stories had previously detailed Ultra Magnus's earlier arrival on Earth and his role in the creation of Metroplex. In "Headmasters", Magnus was a supporting character for the early part of the series, once again in charge of Autobot City on Earth, taking a proactive role in the defense of the planet against the Decepticons when they re-emerged in 2011. During the opening skirmish of the renewed conflict, Magnus crossed swords with the large and powerful Decepticon ninja, Sixshot, who went on to lead the villains' earth-based forces, leading to a smoldering enmity between the two. Their rivalry eventually came to a conclusive end when Sixshot and Magnus engaged in a one-on-one duel. Magnus was no match for the multiple powers of Sixshot's numerous transformations, and was felled by his seventh, secret mode. With his dying gasp, Magnus told the Autobots to protect the Earth. At Metroplex's request, the Autobots buried Magnus on Earth.