Spoilers for Thor #30 by Marvel ComicsIn a look into the past, Marvel Comics just revealed Thor's grandfather Bor and Thanos battled long ago, as the two powerful characters fight changes Marvel history as readers know it. In a new preview for Thor #30 by Marvel Comics, Thor and Runa are shown an echo into the past, where a fight between Bor and Thanos that was lost in time is revealed - and the Mad Titan's arrival might be connected to a seventh Infinity Stone.

In a new preview of Thor #30 by Torunn Gronbekk, Nic Klein, Matt Wilson, and VC's Joe Sabino from Marvel Comics, Thor and Runa's search for Corvus Glaive takes them to a magical wasteland on Asgard, forbidden to everyone, including Odin. They discover a time echo, which shows Thor's grandfather Bor preparing to battle a threat to the realm: Thanos. Bor reveals "the stranger" isn't of their time and that he's come for a reason - with the hint he's after the recently revealed Black Stone. As the fight between Marvel powerhouses begins, Thanos calls out Bor for squandering his powers, asking him what he truly knows about death.

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Thanos and Bor's Battle Hints At The Origin of the Seventh Infinity Stone

The previous issue of Thor hinted at the seventh Infinity Stone being born from the chaos of the most dangerous, forbidden city of Asgard. Bor's sorcerers' attempts to create a weapon with the power to control life and death were seemingly interrupted by Thanos' attack, as amid their fight, a volcano erupted and, combined with dark magic, could have led to the Black Stone. It could explain why Thanos traveled back in time to fight Bor.

Considering Thor has seen dark visions of his death featuring Thanos wielding seven Infinity Stones and leading an undead army similar to the one in the forbidden city of Asgard, it's possible Bor vs. Thanos set the stage for the most powerful version of the Mad Titan in the Marvel Universe. The battle could have led to the creation of the Black Stone, which Corvus Glaive is seemingly trying to use to bring Thanos back to life.

No matter the outcome of Bor vs. Thanos' fight, the supervillain taking on the Asgardian God hints at the secret history of the seventh Infinity Stone, as readers will soon find out more about how the two powerful characters' last battle may have played an important factor in the creation of the Black Stone. Thanos takes on Thor's grandfather in Thor #30 by Marvel Comics, which is in comic book stores on Wednesday.

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