WARNING: The following contains spoilers for Young Justice: Phantoms Episode 10, "Nomed Esir!," streaming now on HBO Max.

Young Justice has always been an ambitious show, with a cast and mythology constantly expanding and practically promising DC fans that they will get to see their favorite hero sooner than later. As the latest story arc focuses on the more mystical side of Earth-16, with a cosmic battle between order and chaos, the magician Zatanna and her young trainees find themselves in over their heads and needing help. Luckily, they have the perfect ally: Etrigan the Demon.

As one of the most powerful (and most fun) mystical characters in DC's repertoire, Etrigan's arrival comes just in time. The heroes of Young Justice need all the help they can get, and Etrigan has all the experience the young spellcasters could ask for.

RELATED: Young Justice Hints A Magical Hero Holds A Dark Secret

The new season of Young Justice implements a new story structure that diverges from the previous three seasons, with Phantoms divided primarily into arcs that focus on different characters and different pieces of the universe the heroes inhabit. While the first arc focused on a Martian plot with M'gann and Superboy at its center and the next looked at the shadowy League of Assassins as Tigress navigated their intrigue, the newest arc focuses on the spellcaster Zatanna as her training of magical protégés gets interrupted by a cosmic duel between order and chaos itself. When the cosmic being the Stranger arrives to recruit their help, it becomes clear that Zatanna and co. need some help themselves. They find the perfect ally in Jason Blood.

The Stranger whisks Zatanna's protégés to Blood's private study, filled with magical artifacts he needs to repeatedly remind Mary Marvel not to touch. Blood proves familiar with the cosmic battle the heroes are new to, but his expertise is not what the heroes need so much as his power. The Stranger pressures Blood into releasing the demon contained within his mortal form, and he delivers his iconic incantation: "Gone! Gone, the form of man. Rise the Demon, Etrigan!" Blood then transforms into a monstrous being that can provide the muscle the heroes currently lack.

RELATED: Young Justice: Beast Boy May Have Found a Cure For His Depression

Etrigan the Demon has a long history in DC comics dating back to his debut in 1972, a Jack Kirby original who is a frequent supporting character in the DC universe's more mystical story arcs. In Young Justice, as in the comics, Etrigan is the demonic half-brother of Merlin, the magician from Arthurian legend. With his soul bound to the mortal Jason Blood through a curse, making Blood effectively immortal, the two share a sort of Bruce Banner/Hulk dynamic, where the human delivers the brain and expertise while the monster has all the brawn and raw power a heroic team can ask for.

Frankly, the stakes are bigger than ever in Young Justice. After revealing the Lord of Chaos, Klarion the Witch Boy, struck a deal with Vandal Savage millennia ago that destroyed a continent by sinking Atlantis, the other Lords of Chaos take issue with Klarion's deal because it wasn't chaotic enough. Wielding even more power than Klarion himself, the Lords of Chaos seem ready to destroy the entire planet and the threat they pose is serious enough that Savage ends the episode by ordering all items of value to be moved off-world. This is exactly the kind of time where the heroes need to pull out all the magical muscle they have, and toward that end, few can hold a candle to Etrigan. Etrigan goes toe-to-toe with the newly arrived Lord of Chaos, skeletonizing her with his fire breath and trading blows with her familiar, Flaw.

RELATED: Young Justice Confirms Vandal Savage Isn't the Most Sadistic Villain - and Redefines the Light

Ultimately, even his efforts prove ineffectual, however, showing just how grand the threat Earth faces truly is. In combating the Lords of Chaos, Etrigan's raw power may not be enough. Blood's magical expertise could prove just as valuable, and if ever there were a time to utilize the artifacts he warned Mary Marvel against touching, this is it.

More importantly to the viewer than anything else, Etrigan and Blood are just fun additions to the cast. Etrigan's rhyming speech patterns always make for creative and unique dialogue, and there is a wealth of fun backstory to be had in the centuries-long life of a cursed man wandering the Earth since Arthurian times, bearing the burden of such a demon. As Young Justice continues to explore its world, this is the perfect character to delve into the background of.

New episodes of Young Justice air Thursdays on HBO Max.

KEEP READING: Young Justice's New Mystical Threat Might Be Its Deadliest Yet