Something bad may happen to Barry Allen (Grant Gustin) in The Flash Season 6 due to the ultimate crossover "Crisis on Infinite Earths." The fastest man alive is about to face a new enemy as reports say the show is now looking for an actor to play the role. Who can be the next villain and the star who will portray it?

Barry has faced several enemies through the show's five seasons. The series already brought in the known big villains, but there is one character that viewers have yet to see - Anti-Monitor.

According to Cinema Blend, Anti-Monitor is the reason why The Monitor puts the heroes to the test in the comics. The villain wants these heroes to face a "significant challenge" to prepare them for his big plan.

However, it is not yet revealed if the "Crisis on Infinite Earths" crossover would introduce Anti-Monitor. It is also yet to be seen if the show will even play the part. But if ever The CW chooses him as the biggest villain, he may first appear in The Flash Season 6.

There are also claims the new big bad can be Evan McCulloch or the Mirror Master. Although the previous season finale didn't tease who will be the next villain is, his mirror gun technology has been used in the last few episodes on the battle against Cicada II.

It is also possible the Red Death will make way to The Flash Season 6 after the character was teased in the earlier part of the previous season. "Red Death is pretty big," outgoing showrunner Todd Helbing told Comic Book. "I think you can tell the bigger characters when we talk about them that we don't do that just as a one-off little Easter egg."

Helbing admitted they introduce characters with the possibility that they might appear on the show in the future. Although it was a tricky thing to do with DC, they made sure they talked to the firm when they started planning.

He also revealed there are a lot of aspects to it, but they always have a way to try to make it work. He also said it is tricky, but he would never say "never."

Meanwhile, Helbing revealed, when he read and saw the pilot, he assumed the "Crisis on Infinite Earths" would be The Flash Season 6 finale. He even teased that he liked it and there are so many things they could do after it.

The executive producer added it is nice to get to the "Crisis on Infinite Earths" sooner than later, and it has changed his view of the show. The crossover would inject a new sense of energy into The Flash Season 6 when it returns in the fall that would be perfect timing for everyone.