According to the studio, Otherworld will include a core storyline that can be played through freely - meaning there won't be a structured quest-line. NPC's will likewise have their own storylines and personalities, all of which will be composed of elements that are selected at random and rearranged through every playthrough.
In order to progress through the storyline, the player will be tasked with finding, crafting and activating "Purifying Towers" that act as a defensive measure to push back the Corruption. Towers attract enemies, which means that players will have to construct customizable Wartowers to protect them.
The game will also feature skill trees that will allow for more control over your progress in the game, with skills and items improving over time with use.
Terraria: Otherworld is currently in development for Mac and Windows PC, while Re-Logic is still contemplating self-publishing the game on PlayStation 4 and Xbox One.
Otherworld, which was confirmed with the unveiling of a newly-launched website, isn't a sequel. Instead, it is being described as an offshoot of the original release. Terraria: Otherworld is set in an alternate dimension within the Terraria universe and will explore what "might have been" according to the official site.
A video of the upcoming title shows a darker, more science-fiction oriented title compared to brighter sandbox world of Terraria; and likewise, it is said to put the player in a "life-and-death struggle to restore a once-pristine world." You can take a look at the trailer below.