For longtime fans of the Young Justice animated series, that phrase brings back good memories. It was the way the youthful heroes anticipated their graduation from sidekick status to full heroes.
Over the two previous seasons of this series, the group of four has changed, grown, and suffered loss. This series has been inarguably one of the best animated action series ever. The quality of the story telling and characterization has always been extremely high. When it was cancelled for spurious reasons, fans were devastated. However, it is back.