The Assassination of Laufey was a successful attempt by Loki to kill Laufey by luring him to Asgard with the promise of the opportunity for him to kill Odin.
Background[]
- "I will conceal you and a handful of your soldiers, lead you into Odin's chambers, and you can slay him where lies."
"Why not kill him yourself?"
"I suspect that the Asgardians would not take kindly to a king who had murdered his predecessor. Once Odin is dead, I will return the Casket to you and you can return Jotunheim to all its... glory." - ―Loki and Laufey[src]

Loki visited Laufey on Jotunheim, and arranged a deal for Loki to lead Laufey and his army into Asgard to kill Odin while he was vulnerable.

Loki released the Destroyer and sent it to Earth to kill Thor and his allies. Heimdall, suspicious of Loki's actions, confronted Loki, who froze him using the Casket of Ancient Winters. With Heimdall out of the way, Loki was able to use the Bifrost to bring Laufey and the Frost Giants to Asgard.[4]
Assassination[]

Heimdall breaks free
Laufey left Grundroth and another Frost Giant to guard Himinbjorg and the frozen Heimdall. Having defeated the Destroyer and learned of Loki's plans, Thor called out to Heimdall, who was able to break free from the ice and kill the two guards before bringing Thor and his allies back to Asgard.

Loki led Laufey to Odin's chamber in the Royal Palace of Valaskjalf, where Odin laid unconscious. Laufey fought off Frigga and an Einherjar soldier and then approached the defenseless Odin. Laufey taunted Odin before Loki betrayed Laufey, shooting him with Gungnir to stop him from killing Odin. With a second blast from Gungnir, Loki killed Laufey.[4]
Aftermath[]

Unaware that Laufey's attack was part of Loki's plot to take over the throne, Frigga praised her son for saving Odin's life. Thor arrived moments after Laufey's death. Thor revealed Loki's true intentions to their mother. Loki blasted Thor aside, and raced to Himinbjorg to use the Bifrost to destroy Jotunheim. Thor was able to prevent the destruction of Jotunheim and the Frost Giants by destroying the Rainbow Bridge.
With the bridge destroyed, Thor and Loki began to fall into the abyss, but were saved just in time by Odin, who had just awoken from his Odinsleep. Loki pleaded with Odin to understand the reason for his actions, but Odin rejected his pleas, and Loki let go, allowing himself to fall to his apparent death.[4]