Eobard Thawne

Now we're talking! Eobard Thawne is the most famous villain here, and simply beating him in the first season just doesn't seem like a very good idea. The whole point of the Reverse Flash is that he somehow always catches up to the real Flash "“ he is simply a problem that cannot be outrun and will continue to persist, no matter what.

So, it can be Eobard Thawne from Earth-2, or from the future again. In the end, who cares. When it comes to explaining these paradoxes everyone has a hard time understanding exactly what is going on. Since we saw the real Eobard Thawne only during the very end of season 1, it would seem logical that we see more of him during season 2. Eobard Thawne and Barry Allen are sworn enemies, so it seems like a very likely scenario.