Who will be the villain for the 6th movie?

Wiseman revealed that there will be a 6th movie, once again staring Kate as Selene. So who is the villain going to be. Well, I have a theory on this.

Before Rise of the Lycans came out, Greg Cox (who did the novelization for the movies), wrote his own prequel called Underworld: Blood Enemy. In it, it's revealed that Marcus had a son who was initially engaged to Sanja. The plot was very different from Rise of the Lycans, and Sanja was very dainty and not a warrior at all. Anyway, when Rise of the Lycans came out, it obviously made Blood Enemy non-canon, but still, the thought of Marcus having a son is interesting.

So far, Viktor had a daughter, and Amelia had a secret son. Is it too farfetched to think that Marcus would have a child as well. Perhaps he could be in hibernation, or ruling another coven, or was banished, or is just dealing with the humans. There are a lot of reasons to explain his absence. He would also really be the final obstacle Selene would need to overcome to put the past to rest.

Being Marcus' son, he too would be able to become a hybrid. At this point, regular vampires and lycans are no match for Selene, Eve, or Michael (who could still be alive). So the villain would have to be too. Knowing he would be no match for Selene otherwise, and feeling that he should be the true ruler, he should go after both Selene and Eve (who has apparently come out of hiding). He could get both at the end at turn into a super hybrid, maybe already having been modified by technology the way Quint was. It's really the only way to make him stronger than Eve. Imagine that as a final battle, a giant super hybrid that now has Selene's spiritual power (assuming that can be inherited through the drinking of blood too). He'd be nearly unstoppable.

Now here's an idea for an ending to the series. During the final battle where Selene, Eve, David, and Lena are trying to fight Marcus' son, Michael suddenly arrives, revealing he's alive. And no, that's not a stretch. He survived getting a metal pole stabbed through his heart in Evolution (although it did take a few hours for him to recover, during which he was in a death-like coma), I'm sure he can survive having his throat slit. Selene only ASSUMED he died, and Marius let her think that to get to her. Or maybe Marius even thought Michael was dead because he entered in that near-death coma again while he was actually healing. They wouldn't even need to use Speedman, as they could just have him be in hybrid form. Together, they defeat Marcus' son, finally ending everything once and for all.

This would wrap up the series, and bring everything full circle. Selene would also finally have a family again to replace the one she lost so long ago. With Michael's return, it would close the door on any chance of romance between David and Selene. I don't like the idea of them being together, as it feel s like it undermines Selene's entire relationship with Michael, which has basically been the driving force of at least two of the movies. Besides, even though David revealed that he has an interest in Selene, she's only viewed him as an ally (at most a friend). But I have a solution for that too. It may have just been me, but I did see a little something between David and Lena.

I'm rambling at this point. So does anyone have any thoughts on the possibility of Marcus having a son (or even a daughter) who's the villain of the 6th (and last) movie?