There was a time when Re-Logic would hang the hat on Terraria years ago, instead of bringing years of updates and content to fans as it transforms into the modern Terraria we know today hui. The old version of Terraria is certainly not bad, to see, but it absolutely does not have the miasma of content and discovery that the modern version presents for Metroidvania lovers.
As they planned to finalize the game, work began on a new Terraria called Terraria: Otherworld. Re-Logic Offers To Release Terraria: Otherworld As Open-Source If A Petition Reaches 100k Signatures.
The project was finally abandoned after the studio had worked on it a bit, then realized that they could do a lot more with standard Terraria without having to develop new libraries and new GUI mechanics. Terraria: Otherworld was never made, and Terraria has become a rugged indie darling we know today.