Ulik was a member of the race of Rock Trolls and lived within caverns called the Realm Below in the extra-dimensional realm of Asgard.
He came to Earth using the Asgardian weapon called Codgel. Ulik travelled to Midgard and using the powerful weapon he battled Thor and the Avengers in New York. The team took him down but in the process lost the weapon, which ended up in the hands of Doctor Doom. Ulik was taken back to Avengers Tower where he was held in a cell. Doctor Doom used the weapon with a few upgrades to release the Midgard Serpent which he planned to use to conquer the Earth. However the beast was to powerful and would eventually grow in size until it consumed the Earth. Using a combined effort they used the extra-dimensional portal used by Ulik to banish the creature to the Realm Below.