Complete story — includes the ending
During an alien invasion, the Team face the ultimate challenge when they are forced to replace the fallen Justice League. However, the Team later learns that the invasion was a mental training simulation containing an unwinnable scenario held by Martian Manhunter, and Miss Martian's powers caused them to forget that the experience was a simulation. Martian Manhunter reveals that his niece is probably the strongest psychic of all Martians; considerably stronger than he.
Sources and content license
Source and revision history · Adapted from Wikipedia contributors, List of Young Justice episodes. HTML formatting and reference markers removed. · Content license