Re-logic have made it clear that Terraria: Otherworld is not Terraria 2, but more of a Terraria spin-off.
Terraria sure has come a long way since three years ago, when developer Re-logic all but abandoned the title. It has since gotten a boatload of updates, and even a PS Vita version, and has benefited from a resurgence in popularity. Now, it looks like Re-logic is ready to make a successor... though it isn't the full-blown Terraria sequel we've heard about.
Terraria: Otherworld is, in Re-logic's own words, a new game in the Terraria universe. What it isn't is Terraria 2, but rather a slightly different type of sandbox game set in an alternate dimension to the original. You can check out the reveal trailer above, which while certainly having that familiar Terraria engine, does have a lot more of a "smoother" and "darker" feel to it.
"Combining elements of sandbox gameplay with role-playing and strategy elements, Terraria: Otherworld explores the Terraria experience in an innovative and unique way - providing a fresh approach to the "open world" genre," said Re-logic in an official blog post.
"Terraria: Otherworld places the player in a life-and-death struggle to restore a once-pristine world - now overrun by a malevolent force that has corrupted nature itself - to its original splendor."
So, it looks like this game will be kind of a "Terraria 1.5". We don't have any information on when, or what platforms, it will release on at this stage, but can expect Re-logic to update us in the near future.