Warning: Contains SPOILERS for The Immortal Thor #11! Marvel Comics fans are fairly familiar with Thor and Loki’s many siblings, as they’ve been popping up here and there in Thor comics for the last few decades. But, for those that aren’t, Thor’s latest comic series gave fans a nice refresher, as Thor has called all his siblings to Asgard for an important mission. Well, except one, who actually showed up to this gathering uninvited by Thor, marking his official Marvel Comics debut. And this god, the ‘God of Doom’, is absolutely terrifying.

In The Immortal Thor #11 by Al Ewing and Valentina Pinti, Thor and his siblings are gathered in Ullr’s Hall on Asgard, as they are about to embark on a dangerous mission: finding their lost brother, Tyr. Tyr, the God of War, has gone missing, and it’s up to his siblings to find him. However, before Thor and his team of all-god warriors dubbed the Children of Odin set off to find Tyr, they’re joined by an uninvited (and utterly terrifying) guest: their brother, Ullr, the God of Doom.

Ullr arrives in his own hall uninvited by his siblings gathered there, only to be their one and only shot at finding Tyr. Ullr is identified as the God of Doom by Bragi, the original God of Poems and Stories, before Loki effectively took his role. It was also Bragi who invited Ullr, and it is he who warns the others of Ullr’s power. While readers aren’t shown the horror of Ullr’s true nature to its fullest extent, anyone whose name Thor is nervous to utter (and never has in his Marvel Comics history) is one worthy of fear, indeed.

Ullr, the God of Doom, is Thor’s Only Chance at Finding Tyr

Ullr is introduced as the God of Doom, but he also goes by another name: Ullr the Wanderer. As explained in this issue, Ullr is one who wanders seemingly aimlessly through the many realms he has access to. He creates portals with his godly power, and travels wherever he desires, presumably bringing chaos and despair with him (given his reputation). It is for this reason that Ullr knew exactly where Tyr was being kept, and who had captured him.

Ullr opens a portal from his hall on Asgard to a labyrinth of Skinner Boxes belonging to the In-Betweener, an entity that acts as an intermediate between the ‘science’ and ‘magic’ aspects of Marvel’s cosmic gods (as detailed in the ongoing series G.O.D.S.). Tyr is being kept within a Skinner Box, as the In-Betweener is attempting to reprogram him by teaching him ‘the ways of Oblivion’ – which is knowledge that could prove very dangerous in the hands of a God of War.

Despite Being a God of Doom, Thor’s Brother Ullr May Have Saved the Marvel Universe

If not for Ullr, the Children of Odin may not have been able to get to Tyr in time, especially given that there was a traitor in their midst all along: Loki. Loki gave Tyr to the In-Betweener in the hopes that the cosmic entity would imprison him forever. It wasn’t until Ullr brought everyone to the Skinner Box Labyrinth that the true magnitude of the situation was revealed. If Ullr wasn’t involved, Loki would’ve worked against the Children of Odin, since they got rid of Tyr to begin with, allowing the In-Betweener to turn Tyr into a true monster.

While only time will tell if Ullr got the Children of Odin to Tyr in time before the In-Betweener turned him into something cosmically dangerous, he certainly gave his siblings a better shot than they would have had without him. This proves that, even though Ullr’s terrifying reputation preceded him, he actually made his Marvel Comics debut as a true hero that may have just saved the Marvel Universe (despite Loki’s meddling), making Ullr a worthy (albeit still terrifying) sibling of the Mighty Thor.

The Immortal Thor #11 by Marvel Comics is available now.