Board Thread:General Discussion/@comment-27464043-20151230192612/@comment-1487677-20180302015455

Im pretty sure odin's spear can also open the bifrost. If i recall loki used it to send the destroyer to earth to attack thor. Thor ragnorok has a lot of plot holes regarding the bifrost, like Hela not using the space stone to open portals to other worlds or using odin's spear.