We are then taken back to the cosmos in the third installment of the Thor storyline- Ragnarok. Ragnarok in Norse mythology is the end of all things, equivalent to the Apocalypse found in the Christian Bible.  

Thor has been searching for all 6 Infinity Stones due to the vision that he had on Earth and left after the Battle of Sokovia, but the search was in vain. While searching in the realm of Muspelheim, he crosses paths with the fire demon Surtur. Surtur proclaims that according to the prophecy he shall lay waste to Asgard and bring about its complete destruction once he unites his crown with the Eternal Flame in Odin’s vault, hence, Thor takes Surtur’s crown to prevent Ragnarok. 

Thor returns home to Asgard and calls Loki out on his deception as Odin and demands to know where Odin really is. Loki takes them to Earth where they find Odin in Norway and here he tells them about the sister they never knew they had- Hela. Hela is the goddess of death and Odin’s firstborn however when Hela’s lust for bloodshed grew too strong, he exiled her to the realm of Niflheim. Now that Odin has lived out the longevity of his life and passes away, Hela confronts Thor and Loki and as they are travelling through the Bifrost to escape Hela back to Asgard, she gives chase and manages to strand them both on the planet of Sakaar while she takes over Asgard. She murders the Warriors Three, countless others, and employs Skurge the Executioner to make him feel purposeful. Skurge has a large role in the comics and is a worthy foe of Thor’s but in this film he is merely relegated as a minion. 

The planet Sakaar is significant because it is the planet Hulk crash lands on in the comics after being exiled by a group called the Illuminati (a group of six heroes assigned to guard and protect each of the 6 Infinity Stones with those heroes being Iron Man, Professor X,  Black Bolt, Namor, Mr. Fantastic, and Dr.Strange) because they felt he was too much of a danger to Earth. We learn that it is ruled by the Grandmaster who is an Elder of the Universe, one of the oldest beings in the universe alongside the Collector, and brothers in the MCU and comics. Thor Ragnarok partially adapts the storyline of Planet Hulk where Hulk is forced to become a gladiator and, in that graphic novel, there are two characters who are also forced to be gladiators who are part of Hulk’s war bound that make an appearance in the film- Korg and Miek. Another significant character is Valkyrie and despite that her real name isn’t explicitly revealed, it is highly implied she is the leader of the Valkyrior (Asgard’s shield-maidens) whose name is Brunhilde. 

Together, Thor, Loki, Valkyrie, Korg, and Miek team up to stop Hela but they are not enough. Thor is even able to summon more of his power as the god of lightning but that still isn’t enough- the only way Thor is able to stop Hela is by having Loki take Surtur’s crown to the Eternal Flame to give life to Surtur as he is the only one powerful enough to kill her and also meaning Asgard’s inevitable peril and doom as the prophecy is fulfilled. 

Although Ragnarok does not connect to the MCU in major ways, it still has connectivity in terms of the vision Thor was shown in his mind when Wanda used a mind hex and saw Heimdall telling him that Asgard would be doomed in Age of Ultron. We also see Thor lose everything he loved throughout his story including his home, his father, his hammer, and his eye, alluding to the comics when Thor had to sacrifice not one but two eyes to gain the wisdom to overcome Ragnarok and becoming more like his father as well as becoming king since Odin has passed. A few last easter eggs from Ragnarok are the appearances of Fenris Wolf who Hela resurrects-  Fenris is the offspring of Loki in the comics and along with Ulik the Giant, and Loki, are the reason why Ragnarok happens; past gladiators that competed on Sakaar include Beta Ray Bill, Man-Thing, Bi-Beast, Ares the Roman god of war, and the Iron Man dragon-foe Fin Fang Foom. 

At the end credits, Thor’s ship is loomed over by an even larger ship, foretelling dire events and the wrath of a titan yet to come.