Brainiac (Blake Ritson) just became Seg-El's greatest weapon in season 2 of Syfy's Krypton. Due to a surprising twist, the classic Superman villain and "big bad" of season 1 may actually be the key to defeating General Zod (Colin Salmon) and restoring Superman's legacy.

After Seg (Cameron Cuffe) and Brainiac escaped from the Phantom Zone in the Krypton season 2 premiere, Seg seemingly killed Brainiac by bludgeoning him to death with a stick, but Brainiac somehow found a way to live on inside of Seg's mind. While being hunted by Lobo (Emmett J. Scanlan), Seg and Adam Strange (Shaun Sipos) found a way to get Brainiac out of his head. However, last week's episode revealed that Brainiac isn't completely gone: Seg discovered that Brainiac's continued presence in his mind is what allowed him to withstand Zod's brainwashing device.

Related: Krypton Teases A Threat Worse Than Zod

In Krypton season 2, episode 5, titled "A Better Yesterday", Seg communicates directly with Brainiac who explains that only an "infinite decimal fragment" of him still exists within Seg. Brainiac tries to help Seg after he is captured by Zod, and Lyta (Georgina Campbell) becomes a hostage of Jax-Ur (Hannah Waddingham). Under Brainiac's direction, Seg attempts to kill Zod. After this fails, Seg is able to escape. When Zod's men intercept him, Brainiac warns him of their exact locations, making it possible for him to kill them all before they can attack.

Brainiac standing still and smiling in Krypton

While Brainiac's advice doesn't help Seg save Lyta, it is the reason he was able to save himself. If Brainiac continues to help Seg, he can be the rebels' trump card in the war against Zod, since he plays an unexpected role that Zod never counted on. This was demonstrated earlier in the episode when Zod experiences a rare moment of confusion. Zod couldn't understand how the "Somatic Reconditioning" program failed to work on Seg. As long as Brainiac being alive in Seg's mind remains a secret, Zod will remain at a disadvantage.

It remains to be seen how Seg's allies will respond when they learn the truth about Brainiac as Krypton season 2 progresses. No one will want to trust the alien who threatened their entire civilization. Of course, it's true that despite Brainiac's usefulness, he cannot be trusted. Brainiac may be an ally for now, but that will surely change if Brainiac acquires a new host. Until then, it will be interesting to see how Brainiac's alliance with Seg plays out, now that Seg's greatest enemy is suddenly the only person who can help him take down Zod.

More: Lobo’s Healing Factor Gave Krypton Its Most Insane Moment Yet

Krypton season 2 continues Wednesdays at 10pm on Syfy.