Heimdall (Earth-11584)

History
Heimdall is an Asgardian citizen and warrior, easily one of the most powerful within Odin's realm. Early in his life he was given the job of gatekeeper of the Bifrost Bridge by Bor, being the first warning for any threat that might enter Asgard or threaten the peace of the Nine Realms. Heimdall earned this position mostly due to his near omniscience and extra-sensory perception, able to see across vast distances of space.

Heimdall's vision was not all-encompassing, however. During Thor's coronation, several Frost Giant's slipped into Asgard unnoticed by Heimdall. Though they were defeated by Odin using the Destroyer, Heimdall was still deeply disturbed by this failure of his sight. So much so, that he allowed Thor and his company to travel to Jotunheim, so that he might figure out how the Frost Giants escaped his gaze. However, he cautioned the group that he might not be able to reopen the Bifrost quickly enough to get them to safety, a prophecy which came true. He did open the bridge for Odin, allowing his king to travel to Jotunheim and save Thor's company of warriors. Heimdall then stood outside the observatory of the Bifrost when Odin used it to banish Thor to Midgard for his transgressions. Heimdall also later watched Thor's failure to recapture his hammer Mjolnir.

After catching the new king of Asgard, Loki, returning from Jotunheim, Heimdall began to suspect that Loki's intentions were not on the up and up. As a result, he turned a blind eye to the Lady Sif and the Warriors Three when they sought to use the Bifrost to travel to Midgard and recover Thor. When confronted with this "betrayal", Loki dismissed Heimdall from his post, freeing him from his oath to serve the king. Heimdall moved to strike Loki with Hofund, but Loki froze him with his innate Frost Giant powers, leaving two Frost Giants from the group he opened the Bifrost too to watch over him. When a restored Thor called out to Heimdall to open the Bifrost for him, Heimdall overpowered Loki's Frost Giant magic and slew his guards, opening the bridge and bringing Thor and company back to Asgard. He was knocked out again by Loki when he tried to use the Siege Engine to destroy Jotunheim, and was powerless to close the Bifrost, forcing Thor to destroy it to save the Nine Realms.

Heimdall's vision then became essential for Asgard to try and police the Nine Realms, as Odin could only muster so much Dark Energy to transport soldiers to various points to maintain the peace. It was Heimdall (and Balder) who alerted Odin and Thor to Loki's activities on Earth involving the Tesseract, forcing the Allfather to send Thor back to Midgard to retrieve the long hidden relic. Heimdall stood watch again, overseeing the repairs on the Bifrost, and studying the Tesseract to speed things along.

More to Come...

Powers & Abilities

 * All-Sight: Heimdall's sensory perception extends far beyond the reach of a normal person, as he can view (and in some cases hear) almost anyone within the Nine Realms (or more appropriately, anyone connected to the Veil of Yggdrasil). His powers also extend beyond the Nine Realms to other places in the universe, such as the Grandmaster's Planet, but it requires great exertion by Heimdall to see that far.
 * Asgardian Physiology: As an Asgardian, Heimdall has a lifespan far beyond that of a normal human being, as well as enhanced strength and endurance.
 * Swordsmanship: Heimdall wields the sword Hofund, which also acts as the key to operating the Bifrost (though this can also be down with Gunginir). This heavy broadsword is described as one of the strongest blades in the universe, incapable of being shattered.

Weaknesses
As all-seeing as Heimdall seemingly is, he is not without flaw. Frost Giants, Dark Elves and Fire Demons have all used secret passageways throughout the Nine Realms to escape his gaze at one point or another, and it is possible that old age has somewhat gotten to Heimdall (though he appears to be close to Thor in age, in reality he is far older, having started his watch towards the end of Bor's reign as king and surviving throughout the entirety of Odin's reign). In addition, though he is a decent warrior, he is not as experienced in outright battle as many of his counterparts.

Film Details
Heimdall appears in the following films within the Earth-11584 continuity. In all cases he is portrayed by actor Idris Elba.
 * Thor (2011)
 * The Avengers (2012) [scene cut]
 * Thor: The Dark World (2013)
 * Avengers: Age of Ultron (2015)
 * Thor: Ragnarok (2017)