Ulik is a fictional character appearing in American comic books published by Marvel Comics. He usually appears as an adversary of Thor. Ulik was created by Stan Lee and Jack Kirby, and first appears in Thor #137 (February 1967).
 Debuting in the Silver Age of Comic Books, Ulik has appeared in over four decades of Marvel continuity, principally as a member of the character Thor's Rogues' Gallery. The character has also appeared in other Marvel-related products including animated television series, toys, and trading cards.
 Writer Mike Conroy commented on Ulik's debut in Thor  #137 (Feb. 1967): "In a strip as steeped in Norse mythology as Marvel's Thor, it was no surprise to come across a troll as big and mean as Ulik." Created as a physical equal for the Thunder God,  the Asgardian troll Ulik became a perennial villain for the hero.
 Ulik belongs to a race of Rock Trolls who live in the dimension of Asgard in the "Domain of Trolls" in Nornheim. Like all trolls, Ulik has an innate hatred of the Asgardians, as they were driven underground by the King of the Norse gods, Odin and forbidden to live on the surface. Being the strongest of his kind, Ulik is commanded by the Rock Troll King, Geirrodur, to steal Thor's enchanted hammer Mjolnir, leading to an extended series of battles with the Thunder God. Ulik proves to be a match for Thor, enhancing his already formidable strength with knuckle dusters made of the metal uru (the same metal of which Mjolnir is composed). He nearly defeats Thor after going into the berserker state of mind but is mystically returned to his realm by Geirrodur when the Asgardians threaten to intervene. He then manages to trap Thor in his Don Blake form; after failing to summon Mjolnir, Blake tells him to strike his cane again. When Ulik does so, Blake suddenly grabs it, transforms into Thor, and defeats him.
 Ulik returns on a regular basis: in one instance, he was bested by Thor and thrown into a deep hole before accidentally waking Odin's former foe Mangog, mistakenly believing that Mangog will help him destroy Asgard after reading an inscription on the prison door left by Odin; aiding Geirrodur once again; kidnapping Thor's mortal love Jane Foster; and battling Thor for possession of a mystic artifact called the Ruby Eye. The character has also travelled to Earth and battled both Thor and Olympian ally Hercules.
 For a time, Ulik fought on the side of several Asgardians who had taken the forms of various humans on Earth. This group included Thor's companions the Warriors Three, Balder, and Sif. He battled a version of Thor called Red Norvell and worked with his temporary allies to escape a Midgard-based technological conspiracy against lost Asgardians.
 Much later, maddened and feral, Ulik is given weapons made from the same forge which created Mjolnir. He becomes the lead in Loki's attack on Asgard; this snowballs into the true Ragnarok. Ulik perishes early on in the battles. A child's hammer, made of troll-hurting iron, is thrown into his mouth by Captain America. This results in an explosion that ends his life.
 However, like all of Asgard, Ulik is reformed on Earth. During the "World War Hulks" storyline, Ulik resurfaces and is shown to have gone on a multi-state drinking binge. He ends up destroying a train bridge with the disaster being averted by A-Bomb and Marlo Chandler's Harpy form. When Ulik starts choking Marlo, he is defeated by A-Bomb.
 After Thor dies during the "Fear Itself" storyline, Ulik replaces him as Tanarus, the new Thunder God, endorsed by the All-Mothers of the Vanir (Freyja, Gaea, and Idunn). Exploiting a glamour charm given by Karnilla the Norn Queen and the circumstances of Thor's death, Ulik is able to retroactively place himself in Thor's place, rewriting history in the process. Only a few individuals like Karnilla and the current juvenile incarnation of Loki are aware of the deception. Tanarus' blunt nature in contrast to the honor of the true Thor allows Heimdall and Sif to realize that something is wrong relatively quickly, culminating in the returned Thor defeating "Tanarus" after his resurrection with relative ease.
 Ulik later shows up as a consultant to the Minotaur of Roxxon. First, he helps Roxxon destroy Broxton, Oklahoma, right below Asgard, then he offers advice and battle against the Frost Giants of Jotunheim. This failed as the Frost Giants proceeded to take over the Roxxon facility.
 As part of the "All-New, All-Different Marvel," Ulik appears as a member of the Dark Council alongside Malekith the Accursed, the Minotaur, Laufey, and some unnamed Fire Demons.
 Ulik and some of his trolls later appear on the Moon where they are found and encountered by Thor Odinson. After an intense battle, Ulik and the trolls escape.
 A tale told of the ancient past says how a confrontation with Ulik and trolls ultimately led to the formation of Thor's hammer, Mjolnir.
 During the "War of the Realms" storyline, Ulik was present with Malekith as he begins his invasion on Midgard. She-Hulk later fights Ulik and his fellow Rock Trolls.
 Ulik possesses superhuman strength, stamina and durability, and has the ability to see into the infrared range of the spectrum, allowing complete night vision. He is also a superior hand-to-hand combatant. In battle, Ulik uses "pounders", metal bands forged from uru and worn over the hands like brass knuckles.
 In the MC2 imprint title A-Next, a future alternate universe version of Ulik aids Loki's daughter Sylene in temporarily turning Earth into a new version of Asgard.
 In the limited series The Ultimates 3, Thor mentions that Ulik is the smith who forged several weapons for his father, including his hammer Mjolnir. The troll appears in flashback in the prequel miniseries Ultimate Comics: Thor.