The Legion #21

Just after Dreamer warns Kid Quantum about her vision of Darkseid, Legion World is invaded by parademons, who are followed by their master, Darkseid himself. But this invasion is entirely in the Legionnaires' minds, and only Shikari and Sensor are immune. Fleeing their teammates, who see them as the enemy, the pair head for the only working threshold, the one Brainiac 5 was using to try and retrieve Karate Kid and Ferro. Just as they enter the threshold, M'Onel destroys it.