This season on Legends of Tomorrow, the team initially appeared to be dealing not with a villain per se, but with the challenge of cleaning up their own mess in the form of anachronisms. While fixing the various ways they messed up time would have been difficult enough with the interference of Rip Hunter's Time Bureau, it turns out the Legends have a much larger foe in the form of the mysterious Mallus.
But who is Mallus? The Big Bad of season three has been a mysterious figure so far. All we really know thus far is that a follower of the mysterious Mallus is responsible for bringing Kuasa (Tracy Ifeachor) back from the dead. We've also seen that Eleanor Darhk (Courtney Ford) has teamed up with the mysterious villain to bring a much less mysterious bad guy back to life -- her father, Damien Darhk (Neal McDonoguh.) We also know that whoever and whatever Mallus is, he is a big enough threat that Rip (Arthur Darvill) is scared of him, and thanks to the midseason finale we also know that Mallus is trapped somewhere in a cold, dark dimension. Sara (Caity Lotz) was transported there when she grabbed on to Damien Darhk as he attempted to flee, and while Sara was yanked back into reality by Agent Sharpe, Mallus swore that he would soon be free, subjecting the world to unendurable pain.
As we know so little about this mysterious Big Bad, fans have come up with some theories as to who Mallus might really end up being and we have to admit, if even one of these candidates turn out to be the real Mallus, it could be very interesting second half of the season.
The newest member of Team Legends, Zari (Tala Ashe) doesn't seem like the best candidate for Mallus, but there are a few things that hint that she might not be who she seems. First, Zari is a bit of an anarchist when it comes to the team. She doesn't really like to take orders and she tends to do things her own way -- we're specifically referencing her taking Helen of Troy to Themyscira without permission or even getting a second opinion. However, not handling authority well doesn't really mean she's really the bad guy wanting to unleash unendurable pain on the world, but something else does raise a few eyebrows. During "Return of the Mack," Eleanor Darhk needs Zari's totem to complete the ritual that allows her to raise Damien from the dead. While Zari herself may not end up being Mallus, there appears to be a connection there.
Time Master Zaman Druce
During the first season of Legends of Tomorrow, the team was trying to stop Vandal Savage and one of the foes they faced in that mission was Zaman Druce. Zaman was a member of the Time Masters and formerly a friend of Rip Hunter's, but as the season played out it turned out that Druce was an ally of Savage's. He was killed when Leonard Snart sacrificed himself to ensure the massive explosion at the Oculus Wellspring. But it's possible that his "death" really just sent him into a dark dimension much like where Sara was pulled and Zaman's experience as a Time Master as well as his use of the Oculus might give him the ability to control life and death as seen with Kuasa and Damien Darhk. He would also have an axe to grind with both the Legends and Rip Hunter.
Captain Cold/Leonard Snart
This one would be a punch to the gut for both the Legends and fans of the show. One of the few things we know about Mallus is that he exists in every moment in time and given that Snart sacrificed himself in the Oculus explosion, that could very easily describe him. Also, the anachronisms that the Legends have been dealing with this season have thus far only impacted members of the team that interacted with Snart back in season one. Newer additions to the team have not had personal connections like their older teammates have. There's also that thing about Sara describing the Mallus dimension as being cold. With Wentworth Miller exiting the Arrowverse, having him go out as the Big Bad would be an interesting send off.
Legends of Tomorrow is presently on winter hiatus and will return to The CW in February.