WARNING: The following article contains spoilers for "Unknown Factors," Episode 21 of Young Justice: Outsiders, streaming now on DC Universe.

In Young Justice: Outsiders, Darkseid's forces are now coming into the light and unveiling weapons of mass destruction that truly strike fear into the hearts of all heroes. The Justice League previously encountered the war satellite known as the Orphanage, a prison where metahumans were also being kept, in space, hinting Apokolips had a much bigger arsenal than first assumed.

We also saw Granny Goodness' VR-goggles, the Goode Goggles, meant to corrupt teens on Earth, which proves Darkseid's legion knows a thing or two about subtlety, too. However, the latest episode introduces the Young Justice Universe to a brand-new weapon meant to expand his legion, and it's one of the villain's deadliest tools: the X-Pit.

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The X-Pit was introduced by Jack Kirby in 1971's Mister Miracle #2, where we saw Scott Free and Oberon get trapped. It was a physical well, a prison of sorts which doubled as a training camp, where traps would plague those inside. It was meant to turn its prisoners into elite warriors, and was run by Granny Goodness and the robotic Overlord. It even appeared in the Justice League Unlimited episode "The Ties That Bind," which detailed Mister Miracle's past. There, we saw how it unleashed the elements -- fire, lava, ice and wind -- to create the perfect killers who could survive any conditions.

However, while these versions of the X-Pit were more of a physical training ground, Outsiders focuses on the X-Pit as more of a mental conditioning tool. In fact, it's meant to be a brutal form of conversation therapy, which Nightwing and Black Lightning sadly find out as they break into Granny's home using the Mother Box Dreamer left the team.

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This tool was intended to cure Cyborg of his Father Box possession, but seeing as Dreamer didn't return yet, Nightwing uses it to investigate the pings from Granny's living room. He thinks she's storing lethal Apokoliptian tech. Jefferson joins him, albeit reluctantly, on this illegal mission. When they break in, though, comms to Oracle are cut and we see a glowing light envelope the duo, swallowing them up. We don't know where they end up until Kaldur and his boyfriend, Wyynde, come to rescue their friends.

Granny's grateful they're acknowledging the illegal act committed by the duo, and she agrees they've been punished enough. She instructs Overlord to take them below, and we see the trio in a red, transparent cube. However, it's the sight outside the cube that is most shocking, as Dick and Jeff are floating in the pit -- now shaped as an ethereal ocean of light in which its victims are suspended. It looks like they're stuck in a sea of lava, and surprisingly Granny tells the Leaguers they're free to swim out and get their friends from this zone where people who need "correction and discipline" are held.

But when they do so, the conditioning enters their minds and attempts to make them subservient to Darkseid too, along the lines of when folks submit to the Anti-Life Equation. It tells them "Obey your Granny. My command is Darkseid's will" repeatedly, as if to entrance them. However, the Atlanteans have one distinct advantage their allies don't.

Wyynde instructs Aquaman to use his symbolic Atlantean marks and activate their magic. These mystical tattoos help to provide a barrier from the X-Pit and they swim out to bring their friends in. They're barely alive, and when the heroes take their friends back to Granny's living room, a brawl ensues as Dick and Jeff have, indeed, been converted. Luckily, Halo arrives on the scene and uses her Mother Box powers to cure the duo, but by the time the team escapes and returns to base, Dick's suffered the brunt of the trauma. He's in severe anguish as we see Oracle keeping him company, lost as to what he's going through.

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It wasn't prudent to invade their enemy's lair, but no one enjoys seeing Nightwing in this state of disarray. Granny might have been defeated, but she was shrewd enough to figure out a way to leave a lasting impression on at least one of the heroes. Well, until the League finds a way to shut the X-Pit down for good (as it seems they were teleported off-world and maybe into Apokolips), they'll have a lot more of Darkseid's soldiers coming for them, and could run the risk of ending up like Nightwing.

New episodes of Young Justice: Outsiders premiere Tuesdays throughout the summer on DC Universe.