Bifrost (Earth-6531)

"The Bifrost is not the only way in and out of this realm. There are secret paths between the worlds to which even I, with all my gifts, am blind."

- - Heimdall to Loki

The Bifrost, also known as the Rainbow Bridge, is an interstellar portal that enable instantaneous faster-than-light travel to the Nine Realms and other planets across the universe. Guarded by Heimdall, the Bifrost can only activate by Heimdall's sword, Hofund, or Odin's Gungnir. During its activation, the Bifrost evokes magical energy from within Asgard itself, being able to destroy entire planets if not correctly manipulated.