After waking from a nightmare in which Thanos managed to kill Thor and nearly kill Juliet, the Queen suggested that she and Loki use the recently acquired Reverie Blade to re-enter his nightmare, and use the blade to kill Thanos. He was hesitant at first, given as he'd awoken the moment Thanos had grabbed Juliet to kill her, but eventually decided to do as she'd suggested, and left to retrieve the blade. Once done, the couple both held onto the blade, and returned to Loki's nightmare.
Arriving in the nightmare at the exact place it'd left off, Loki stared in horror as Thanos attempted to suffocate Juliet, who in his dream, was not pregnant as she was in reality. He managed to free her, however, by using his Jotun abilities to freeze Thanos' arm, and then sent the Titan hurtling into the wall with a blast of energy, grabbing Juliet and running moments later. In the hallway, Juliet suggested that they hide to come up with a better strategy, but Loki, tired of running from his nightmare, refused and stood his ground, only to have Thanos appear to further mock him for his choice. Standing his ground still, Loki shot a few comments of his own back, and Thanos summoned several members of the Black Order, namely Proxima Midnight, Corvus Glaive, and Ebony Maw, and Thanos demanded that Loki hand over the Tesseract. He gave Loki no chance to do so, however, before Proxima attacked Loki, and he once again, used his Jotun abilities to kill her. Ebony and Corvus then attacked Juliet, but she fought them off, though Loki's distraction allowed for Thanos to toss him across the room, and lose his grip on the Reverie Blade. Stunned and mildly injured, he could only watch as Thanos approached him, and was barely able to get to his feet in time to stop Thanos from strangling him. It was then that Juliet picked up the Blade, and jumped onto Thanos to cause a distraction, dropping the blade nearby for Loki to retrieve. He watched in horror instead, however, as the Titan flung Juliet across the room and into the wall, and only turned to Thanos when he was positive that Juliet had survived her throw. Fueled by rage and the desire for revenge, Loki attacked Thanos, successfully killing him, and thus ending the nightmare, and any further chances of Thanos appearing in his dreams again.