This is the white wood of Feierheim. Every seed, twig and branch were burned and destroyed eons ago. I needed a way to bring it back. The magic of Undrjarn is simple but strong. It turns into what you need, Valkyrie. 
Appearing in "At the End of All Things: Part 2"
Featured Characters:
- Valkyrie (Jane Foster) (Main story and flashback, as well as Thor in recap)
Supporting Characters:
- Spider-Man (Peter Parker)
- Doctor Strange (Stephen Strange)
- Avengers
- Captain America (Steve Rogers)
- Iron Man (Tony Stark) (Voice only)
- Mr. Horse
- King Loki
Antagonists:
- Tyr Odinson (Main story and flashback)
- Rokkva (Main story and flashback)
- All-Father Thor (Main story and recap) (Controlled by the Rokkva)
Other Characters:
- Einherjar (Only in flashback)
- Brunnhilde (Only in flashback)
- Numerous unnamed others (Only in flashback)
- Drrf (Main story and flashback)
- Sif (Referenced)
- Øde (Corpse, skeleton or other remains) (Main story and flashback)
- Loki (Only in recap)
- All-Father Odin (Only in recap)
- Valkyries (Mentioned)
- Volstagg (Only in recap)
- Lisa Halloran (Only in recap)
- Avengers (Recap)
- Vision (Only in recap)
- Captain America (Sam Wilson) (Only in recap)
- FDNY
- NYPD
Races and Species:
- Asgardians (Main story and flashback)
- Boars (Corpse, skeleton or other remains) (Only in flashback)
- Trolls (Mentioned) (Only in flashback)
- Gods (Mentioned)
- Humans (Main story and flashback)
- Frost Giants (Main story and flashback)
- Asgardian-Frost Giant Hybrids (Only in recap)
- Winged Horses
- Horses (Mentioned)
- Dogs (Mentioned)
- Demons (Mentioned)
Locations:
- Niffleheim (Only in flashback)
- Jotunheim (Only in flashback)
- Barren Mountains (Only in flashback)
- Midgard (Earth)
- Telemark, Norway (Mentioned) (Only in flashback)
- United States of America (Main story and recap)
- New York (Main story and recap)
- New York City (Main story and recap)
- Manhattan (Main story and recap)
- Midtown (Only in recap)
- 42nd Street (Only in recap)
- McCarthy Medical Institute (Only in recap)
- Maria Wheelock Cancer Center (Only in recap)
- McCarthy Medical Institute (Only in recap)
- 42nd Street (Only in recap)
- Midtown (Only in recap)
- The Bronx (Mentioned)
- Manhattan (Main story and recap)
- New York City (Main story and recap)
- California (Behind the scenes)
- Los Angeles (Behind the scenes)
- New York (Main story and recap)
- Asgard (Only in recap)
- City of Asgard (Only in recap)
- Feierheim (Mentioned)
Items:
- Undrjarn the All-Weapon (Main story and flashback)
- Urdoor
- Mjolnir (Main story and recap)
- Destroyer arm prosthesis
- Captain America's Uniform and Shield (Main story and recap)
- Falcon's Wings (Only in recap)
- White Wood (First appearance)
- Spider-Man's Suit and Web-Shooters
- Cloak of Levitation and Eye of Agamotto
Synopsis for "At the End of All Things: Part 2"
In Valhalla, Tyr Odinson waits tables for the Einherjar as punishment for his treason against Asgard. Resenting this humiliation, Tyr bides his time by earning the trust of the oldest Einherjar and soliciting tales from them. Learning of the Urdoors, King Øde, and the Røkkva, Tyr formulates a plan for revenge. When Jane Foster pays a visit to Valhalla as the new Valkyrie, Tyr sees in her Undrjarn the All-Weapon as the final piece of his plan. Using the Urdoors to escape to Jotunheim, Tyr travels to the Barren Mountains, exhuming the grave of Øde and finding the tomb of the Røkkva. Unable to open it with conventional means due to the ancient enchantments placed on it, Tyr takes Øde's corpse to Midgard and tries to resurrect him with the Sap of Yggdrasil.
In the present, Valkyrie addresses the Røkkva-corrupted Thor and asks if he can hear her. Worried that he's losing control, she uses the Sight of the Valkyrie in an attempt to see his fate, but finds herself engulfed in darkness and surrounded by scattered fragments of Thor's memories. Confused, she nevertheless urges Thor to fight the Røkkva only to be attacked by him, conjuring a shield of light. Abruptly realizing that the reason she can't see Thor's fate is that the spectre of his death is so massive they're inside it, Valkyrie reluctantly fights back with a conjured mace. Sensing Midgard being consumed by the Røkkva, Valkyrie again urges Thor to resist its corruption only to be blasted by blackened lightning. The Røkkva attempts to infect her as well, but Valkyrie resists it and conjures a whip of divine energy, snaring Thor with it and trying to burn the Røkkva out of him. Valkyrie assures herself she can win, but isn't sure she wants to - having died before, Jane notes that the Røkkva's corruption feels nothing like that; and that Thor's lightning is no-longer energy but is draining her power and vitality. Valkyrie notes that she could kill Thor, but it would cost her own life to do so. The Røkkva's corruption takes root in her, corroding her memories and ability to feel emotions. Acting on instinct, Jane releases Thor and regains control of herself, warning Thor that if they keep fighting she'll be forced to kill him. Jane's mental voice tells her to treat the disease rather than the symptoms, but Valkyrie doesn't know how. Undrjarn resonates with her desperation and transforms into a spear of glowing white wood. Noting that despite the weapon's simple appearance it's almost-impossibly heavy, Valkyrie hopes it can do what even Mjolnir couldn't and holds the holy spear over Øde's blackened heart as Thor lunges at her.
On the surface, the Avengers struggle to fend off the Røkkva-manifested monsters. As Spider-Man asks for some help, Captain America says he can feel something happening and asks Iron Man what his sensors display. Iron Man replies that he's detecting massive movement in the Earth's core, and that whatever it is it's big. Abruptly, the Røkkva-manifested monsters let out ear-splitting howls of agony as Valkyrie's white wood spear pierces Øde's blackened heart - unleashing a shockwave of holy energy that blasts Thor back and cleanses the Earth of the Røkkva's corruption.
As Valkyrie collapses from exhaustion against the slab where Øde's bones sit, cleansed of the eldritch darkness, Tyr steps from his hiding place and takes Undrjarn - still in the form of a white wood spear. Saying he didn't expect to see Thor - who is still corrupted - there, Tyr thanks him for weakening Valkyrie and quips he thought he'd have to cut Jane's arm off. Transformed back into her mortal form, Jane berates Tyr, who remarks that he should have known she was the new Valkyrie. Tyr gloatingly explains that Undrjarn's power is to transform into whatever Valkyrie needs, and that the only thing capable of purging the Røkkva's corruption is the holy White Wood of Feierheim, long since made extinct. Stating that he had tried to resurrect Øde order to get Undrjarn to transform into a weapon made of the White Wood, Tyr smugly gloats that Jane behaved exactly as he predicted.
On the surface, Mr. Horse notes that something isn't right, Spider-Man asking what he means as they watch Doctor Strange help one of the victims - who states it's like all the joy and hope has been sucked out of his body. As Doctor Strange tries to console the man, Spider-Man wonders if Valkyrie could be hurt; Mr. Horse saying he'll go down after her but that he doesn't do so good underground. The man asks if what's happened to him is magic, Doctor Strange remarking that he's not sure but gets the sense that it's one of the oldest magics in the universe.
In Jotunheim, Darf the Frost Giant alerts King Loki to the sudden appearance of Tyr and Thor. Loki asks if they appeared using the Bifrost, dismissing Darf's warnings of great evil in the Barren Mountains as nothing more than old superstitions.
Jane Foster regains consciousness to find Mr. Horse standing over her, who grumps about not getting his daily serving of hay before congratulating her for saving the world. Jane states that she needs to go to Asgard, Mr. Horse agrees to take her there but asks that she not make him team up with the other flying horses.
As Tyr and Thor reach the Tomb of the Røkkva, Loki confronts them before gleefully noting Thor's corrupted state and asking how Tyr got him to be so obedient and quiet. Tyr snaps at Loki to leave, but Loki remarks that nothing - not even Mjolnir - can break the Seal of Feierheim, and that if Tyr believes the old stories he's insane for wanting to do so. Tyr remarks that the oldest forces of the universe were sealed away in ancient times because not even the gods couldn't be trusted with that power. Raising the white wood spear, Tyr snarls that it's unfair that the gods should be left to squabble amongst themselves barely more powerful than the mortals they preside over; Loki snarking that the gods do have superhuman strength, immortality, and various forms of magic. Snarling that for there to be true peace one god must rule above all others as a true All-Father, Tyr stabs the white wood spear into the seal, gouging it - to Loki's horror. Tyr orders Thor to strike, the blackened God of Thunder throwing Mjolnir. Barely managing to teleport out of the way, Loki picks himself up and grins as he wonders what his brothers have gotten themselves into.
Stepping into the Tomb of the Røkkva, Tyr feels a brief moment of regret as he realizes the Røkkva - a primordial entity of antilife - may be too powerful for even him to control. However, he senses that the Røkkva will obey him as long as he has the white wood spear, and that it's too late to turn back now.
Solicit Synopsis
THE FALL OF ALL-FATHER THOR!
Valkyrie and Thor have discovered a vast and terrible secret buried deep in the Earth, one that has haunted Asgard for eons. The Røkkva, a magic older than the gods, has broken free from its long prison. And one man seeks to turn it to his own gain. He just needs to get rid of Valkyrie first — and what better way than at the hands of Thor?!